Playing alot of games like counter strike where ghosting is a problem, I fail to see how it could be an issue in mount and blade.
You don't have guns that can instantly kill people and everyone can hold the ~ key to look all around them at all times, hardly see how any ambush can take place in this game, its more like oh hey I see you now I either engage you in melee dodge your arrows hear your hoofsteps or I'm already using ~ and can see this lancer coming behind me.
Now a game like counter strike I can be appearing my head up in long hall on office and get awped and die instantly. This could have been prevented by a dead teamate telling me a sniper was watching that hallway, but even in counter strike not all servers have locked spectating.
Ghosting could have some effect in crpg but I believe it would actually matter so little it wouldnt even matter or change the battle. Crpg is more about watching the superstars fight whether they are on your team or not and being able to see a battle unfold, this is suppost to be more of two armies fighting eachother shouting curses instead of people camping corners with automatics and sniper rifles armed with flashbangs.
Now strategus? maybe it could effect the outcome with more strategized play, but even still whether you ambush a guy or not you get no bonus for charging someone if they block you will still have to fight them in melee and defend and attack, unless your a ninja from behind or have some cavalry waiting in an odd position or ranged? The players will still be able to register you so fast I don't think it would phase their performance.