What I like about this is it forces your opponent to attack what he wants crumble to affect. That's pretty cool. There is a bit more keeping track of specific wounds dealt during that combat, but its not to terrible.I think crumble as it is now denies the flavor of the game.
Which is to use multiple units to out maneuver flank rear ect.. You just don't do that under the current crumble system. I remember when the VC player assigned the extra wounds where he wanted however this would make a VC buss invulnerable because you would just keep subtracting wounds from zombies even if your buss got its face pounded in.
I think an more equatable and fair system would be to allow for wounds taken only to equal what was lost by each individual unit.
Here is an example.......
You charge the front of a unit with 50 zombies with banner and the rear of said same unit with 4 ranks and banner with a single varghalf.. The combat pursues with you doing 0 wounds from the zombies and 4 wounds from the varghalf the enemy does 22 wounds to your zombies 1 to your varghalf.
So the totals for you are +1 charge +2 Rear +3 zombie rank +1 Banner +4 wounds = 11
The totals for your enemy are +1 Banner +3 rank +23 wounds = 27
27-11 = you loose by 16... your opponent stands his ground and now you crumble.. Now here is the change
The zombie loose 16 wounds however the Varghalf only looses 1 wound because he only gave up one..
Nothing earth shattering but a more fair a flavorful change IMO.