Doesn't seem like a fun mechanic, though I rarely ever play cavalry anyway.
There are a lot of things in warband that don't make sense, but the alternative is anti-fun gameplay due to engine limitations.
Here's my list of unrealistic mechanics that kind of need to stay for combat to remain "fun":
Getting hit by a plated charger at full speed doesn't instantly KO/kill everyone.
Full plate isn't basically invulnerable to most attacks.
Shield forcefields vs projectiles.
Block forcefields in general for melee.
Throwing lances don't take people in chainmail or under out of action on leg/chest hit.
Super duper permagrip until death on melee weapons, no slipping from rain.
Rigid swords and daggers don't get ruined if hit by a bar mace, mauls don't knock weapons out of people's hands.
No arm/leg crippling.
Staves/axe handles never break.
Axes/picks/morningstars never get stuck inside people/shields.
Steel shields/really heavy pommel strikes deal zero damage to people in chainmail/leather, even if you hit them in the face.
Weapons don't get stuck inside dirt/walls.
Infinite stamina, no sprinting.
I don't think something like this would be a good mechanic. It punishes you for hitting the enemy.
It's not a punishment, it's a tradeoff. You have the ability to land a very powerful, unblockable hit (in case of both couched lance and 1h/2h against a horse) but you might lose your weapon in the process. (Making proper sidearms a useful thing for cav)
Well.... cant belieave im reading this shit post from devs.....
So..... more nerfing shit incomming?? srly ??
While you at it, using realism as argument.. make plate immune to cut weapons, implement sprinting, make all wooden weapons breakable, make horses able to kill players when bumping at full speed, make arrow quivers realistic and give them lower ammo ect etc etc ... i could go on an on....
I really hope the devs won't just implement this as cav nerf, but instead use the idea to enhance the way cavalry works in c-rpg now.
As for the realism... Dropping your lance upon hitting your opponent at high speed is not realistic. Having it break, leaving half of the lance stuck in the opponent's dead corpse would be realistic :P I hoped this mechanic could 'open doors' for some actual changes to cavalry (for example making it more powerful, but harder to play)