How can I perform a tactical withdrawal?

[J.Alco]

Well this happened to me in RTW Vanilla, not EB, but I think the principle of the tactic is sound:

Basically, I had an outnumbered Roman army fighting a vastly superior Germanic army (I was outclassed in numbers and quality of troops). I thought I might as well give the battle a shot and see what I could do. I arranged my troops in several lines, taking loose inspiration from Roman formations. The first line was composed of Town Watch, the second by a mix of Hastati and Principes, another by Triarii, and the final line had my archers, skirmishers, and my general's unit (I had no cavalry, but neither did the Germanic army).

Thanks (Oh thanks) to classic RTW AI, the enemy army didn't even try to flank me, instead just marching forward into my lines in a classic 'punch through the centre' genius move it often makes. My archers fired on the advancing troops, and when the germans hit the Town Watch, who were holding ground, I ordered them to cease fire and sent my skirmishers forward to pelt the enemy from behind my lines. When it looked like that wasn't going to do anything, I sent the second line forward, and then finally my third, and finally the out-of-ammo skirmishers. In the meanwhile my general kept darting around the enemy flanks and rear, charging and moving out and charging again. After a while it was clear that it wasn't going to work (There were simply too many of them), so I started a gradual retreat. I pulled my general back to a safe position behind the lines, then pulled back the militia with the 'withdraw' command and made sure they kept running, before repeating the same process with the Hastati/Principes, followed by the Triarii, and finally the skirmishers (I could be getting the order wrong there). As my troops were relatively fresh, or at least fresher than the enemy, they were able to outpace the Germanic army suspiciously quickly while my archers kept firing into the Germanic units (the bulk of their army was those slow-moving pseudo-phalanxes, which make great targets), moving back every so often to keep a good distance. When they were out of ammo, I withdrew the archers and the General, who I'd kept on the field to rally any units that might have broken into a rout.

I was actually rather proud of that maneouvre. A practically textbook example of a fighting retreat.

Unfortunately I can't guarantee it'll work for EB, for several reasons:
-You need prime conditions for it, in my case an enemy army with no cavalry and alot of slow-moving infantry.
-The EB AI is much more fond of flanking maneouvres, so taking up a 3 (or more)-line formation will probably be a big risk with regards to losing versatility.
-In the end the enemy lost as many troops as I had, and that was probably because alot of my troops were killed as they withdrew, so high losses are inevitable.

As I said, that's how I fought a tactical withdrawal, and ended with my force relatively intact. I can't vouche for its effectiveness in EB though, but like I said: The principle is sound.