New(?) Cavalry tactic/exploit

[caravel]

So, I have noticed that when you put a high-charge(relatively) cavalry unit (e.g. mounted sergeants, feudal knights or Armenian heavy cav) in a single line and hold formation, then charge it at enemy unit (the formation has to be relatively intact) but at last second switch to Engage at will, it will cause the enemy unit to take heavy casualties and insta-rout. The timing of the switch is important - too late or too early will not yield such dratic results, though it still may work on some weak units.

Yes it works, as a line, not necessarily a single line though - just a wide frontage, it was always a favoured tactic of mine. It has got nothing to do with the swipe bug however is still effective in 2.01 and offsets the "swarm of bees" effect you get when charging units in engage at will mode (the whole mob rush the standard bearer).