I'm leery of the idea of the ability of any shock cavalry to do Jack Manure to formed and steady pikemen with cold steel. I don't care if the Husars had five-meter lances or something; if Parthian and Sassanid cataphracts with their four-meter kontos spears couldn't really even dent the lines of sword-toting Roman infantry and Medieval knights could be seen off by commoner militias and peasant-levy shieldwalls (or often rather haphazardly armed dismounted knights) and so on and so on I don't really see how the Hussars could magically convince their horses to do something no other cavalry force ever managed to goad them into doing regardless of how hard they tried.

Now, the Husaria were pretty good at manuever and not too shabby at feigned flight, and by what little I've seen written of it this is how they demolished the Swedes at Kircholm - lured them out of formation and tore apart with a sudden counterattack. This is credible and sounds like being well within Polish military practices of the time - they did a lot of fighting with pesky steppe armies after all. The supposed ability to frontally engage formed pike-and-shot formations, however, goes directly contrary to everything I've ever read of cavalry warfare and frankly sounds like pure fantasy.

Most European heavy cavalry ended up using the caracole for the pretty specific reason that although it took bloody forever to bring results it at least actually worked against pikemen, which is something no amount of armour or lenght of lance had done. Bet your hoop they tried pretty much everything else too - they had centuries to experiment after all.

As for the pistol vs. lance thing, I would like to point out that even armies who had long maintained effective lancer traditions - the English demi-lancers had proven pretty workable against German Reiters in the Low Countries in the late 1500s for example, and a great many cuirassieurs came from the ranks of nobility who still learned to use the lance if only for tournament jousting (the Swedish Rustkammaren has Gustavus II Adolphus' jousting harness on display...) - seem to have decided the pistol was the better bet, and properly deployed it seems to have served well enough even in head-on clashes with lancers. And this happened within fairly short time after the wheellock pistol became widely available; the way shock-cavalry doctrine started becoming obsessed with cold steel around the same time the pike fell out of use among the infantry can hardly have been a coincidence either.
The second pistol was usually reserved for either pursuit or self-defence in a retreat, after the initial impact if the formation is still dense and unbroken cvalrymen can do little more than either slash each other without much effect (i.e. lock themselves in combat) , retreat and try again ( hard to achieve) or wait untill support arrives to outflank the enemy somehow.
The battlefield formations of the 1600s normally had to clash several times until either one's cohesion and morale was sufficiently worn out that they broke for good. They would advance to contact, clash until one gave ground, retreat and pursue for some distance, reform, catch their breath (and reload, and whatever), and do it all over again. Nothing new under the sun there, this was how field combat had for the most part been done since God knows when. If neither side held any particular advantage and was well disciplined this could drag out for quite a while, and might not actually even get resolved at all unless something drastic - like a supporting flank attack - interwened. In the TYW there were several instances where the battlelines simply hammered at each other for the better part of a day in a grim attrition match - commanders obviously didn't really like doing this since it kind of wasted troops and could go either way.

Lance can be discarted as well, of course if we talk about similar class of weaponry i.e. lighter lance compared to a pistol. Again the question how to receive charge and stay alive isn't much a choice between inaccurate pistol and prety useless heavy lance. Also light lance isn't much useful when facing charging enemy, but lancers aren't created for receiving a charge after all.
Did you know, medieval cavalry actually developed a practice of having the flanks of the squadron wield their swords (or whatever) already during the charge. This was because the lancers were very vulnerable for a brief while immediately after the charge when they were discarding their now-useless pointy things and getting their backup weapons out; the job of the guys with the backups already out was to defend their comrades during this time...

Incidentally, "gun" cavalry could and did receive charges stationary (usually first discharging their carbines at range and then pistols at point-blank distance). How well it worked depended on quite a few factors, but enemy cavalry trying to break into such solid fire-spewing blocks often did find themselves stumped. It should be remembered that even horse-archers have been recorded succesfully facing down heavy cavalry the same way - horses aren't any keener on running headlong into a solid immobile line of other horses than a solid immobile block of men, one imagines.

The answer is it isn't - because we are talking about cavalry using 2 or so pistols and not employing the caracole anymore its wrong to assume that they are much more efficient than lancers.
Firstly because lancers of this period of time had pistols as well so if the lance isn't useful they still had the same choice as reiters - shot them with pistols.
And how exactly are they going to go through the rather complicated procedure of reloading a wheellock while still holding onto the big, unwieldy lance I wonder...? One of the issues with the lance was after all that it pretty much always kept one hand occupied. "Pistoleer" cavalry conversely often also carried carbines for ranged work, and although I don't really know the details I know they were as a rule very thoroughly drilled in unit-level maneuvering; some kind of "mounted counter-march" not entirely unlike the caracole may well have been included in the training regime for dealing with infantry.

Second if we assume that this cavalry has enough time to shoot and reload many times clearly there is something wrong going on - either the enemy already fled leaving most determinated rearguard for some reason without too many musketeers to speak of or its purely theoretical excercise.
Simply cavalry has something else to do than to try to shoot pikemen to bits because it takes a very long time with 1 or even 2 loaded pistols. Dragoons or surely already approaching musketeers are more suitable, besides pikemen left without musketeers are very rare if not impossible to find on a battlefield at that time.
You seem to be missing the point that major field battles with up-to-date "pike and shot" armies often took a long time. In some cases several days, with the troops simply sleeping in their positions. The battlelines could be many kilometers long, and the distances maintained between successive lines of units around a hundred meters or so.

As mentioned before "pistoleer" cavalry commonly also carried carbines, but it is true enough that involving them in a shooting match with infantry formations wasn't generally speaking the most effective way to use them. But it's not like there always was much choice; you formed the line from what you had. AFAIK the full-sized infantry musket kind of tended to outgun and out-range the smaller cavalry carbine too, nevermind now the pistol which was virtually a close-combat weapon anyway (although its effective range against close-packed masses of practically unarmoured footmen was rather longer than against other cavalry in decent armour). On the other hand the cavalry could actually wear enough armour to actually have a measure of protection against incoming fire, and given the abysmal accuracy of smoothbore guns (and the generally less-than-stellar skill of their users) and the way visibility rapidly went to Hell in a handbasket due to the thick clouds of smoke black powder produces the advantage was likely somewhat relative. In any case, one imagines the cavalry could employ their maneuverability to compensate by retreating out of range to reload plus they only really had to thin out the pikemen anyway; once those were sufficiently frayed the musketeers were pretty much fair game, after all.

But without doubt commanders would prefer to use their own "shot" - foot or dragoons - for this rather than wasting valuable cavalrymen if at all possible. Or artillery. Regimental guns were often attached to cavalry squadrions too.

Well... quite opposite heavy cavalry was almost lethal to light cavalry ( with the exception of few fortuante or elite regiments and the lancers) and the armour and helmet has much to say why they were so dangerous. Heavy horsemen used bigger steeds, were armoured and recruited big, strong men they were imposing sight and very powerful weapon against infantry or even better against enemy cavalry.
Victories of light cavalry over 'the heavies' are pretty rare events, lancers were able to defeat them because of several factors, first and most important was always the lance itself.
One reads of British "heavy" dragoons and other unarmoured cavalry occasionally trouncing French cuirassieurs, for example. I've read several accounts of the cuirassieur helmet simply splitting under a strong cut, and even without that kind of lucky shot there was always the face and limbs - or the horse - to aim at. Oh, there's no doubt the Napoleonic cuirassieur was a force to be reckoned with; he was an elite heavy cavalryman after all, and his armour hardly hurt any. But hand-to-hand attacks could be aimed at the bits his harness didn't cover rather better than shots at range (which were what his gear was primarily against), and period cavalry fights were also rather more about discipline, morale and unit cohesion than actually killing the enemy soldiers - and while I can hardly claim to be a great expert on the subject what I've read of it seems to suggest cuirassieurs weren't on the whole all that more resilient in those terms than any other higher-end heavies.

Lance wasn't odd idea, the pistol fuelled charge was abandoned rather because of the faster pace of the charging cavalry - pistols were not abandoned after all.
Cavalry charge speed was normally dictated by the need to maintain unit formation and the all-important cohesion. What little I know of it doesn't seem to suggest standard Napoleonic attack paces were much different from those of 17th-century Reiters.
And IIRC not a few armies dumped cavalry pistols altogether within a few decades of the end of the Napoleonic Wars - they had a kind of obsession with armes blanches. 'Course, out in the New World cavalry started not too long later realizing a revolver (and/or shotgun) was a way better shock and melee weapon than some pesky chunk of steel...

And it was a different weapon than the old spears to the same degree as the pistol is no longer javelin thrown before a charge.
Really ? I've seen pictures of those lances. Around two or three meters long, fairly small head, two loops for both carry and to serve as a wrist-strap, right ? They're practically cut-down kontos sarmaticus - even the carrying-loop arrangement harkens back to what the ancient steppe peoples and many of their neighbours used (the lineage to the lances used by the Russian Cossacks around Napoleonic times being obviously pretty direct, for example).
Walks like a duck, quacks like a duck, looks like a duck...

Pistol. Javelin. Largely identical tactical role, different weapon (with the bonus effect of way nastier psychological impact). Bad comparision.

Not really, lances were kept even in 1914, theu were abandoned more because of lower possibility of a battlefield real charge - cavalry became mounted infantry more or less after all.
And worked way better as mounted infantry too on the average, AFAIK. I may be confusing the uhlans with the cuirassieurs here, admittedly - most of those guys lost the armour (except for ceremonial occasions) around the mid-late 1800s and became little different from regular cavalry, but now that I think about it I do seem to recall seeing the odd bunch of lancers in assorted WW1 contexts.


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...incidentally, aren't we hijacking the thread a bit ? "Take us to Alaska or else...!"