At one small skirmish I took part in some years ago at Pendennis I had the joy of being allowed to volunteer to be the guy who took the nasty Norman horseman out of the saddle with a dane-axe. b**ger me but it looked great, and the public roared for the plucky little Saxon.
However, that one piece of action involved 3 people (me, the cavalryman, and the guy who caught the bridle of the loose horse), lasted at least 15 seconds, and took hours to rehearse. To try and do it on any larger scale would be impossible. Plus, I ought to point out that the rider was a sergeant in the Royal Horse Artillery, specially picked to be a part of this display team. With no offense intended to re-enactment riders, I doubt that many of them come up to his level of training and experience.
The authentic use of cavalry in battles is something which has plagued re-enactors since the dawn of time (or at least since authenticity became an issue). Unless you're prepared to start sacrificing horses or the enemy infantry it just can't be done right.
The real question is would it be better to have the cavalry riding round and round the field occasionally going "ting" with anyone who gets in their way and generally looking like posers on nags; or to dispense with the cavalry altogether, fight a more realistic battle, but lose the horsey spectacle?
OR, is there actually some magic way of using cavalry in a convincing manner that has yet to be found?
...and further this Informant saith not.Foxe'Don't be fooled by his general air of living in a skip'http://www.etfox.co.uk