I have tried to make these work ever since WFA was released. From my extensive experiments with the mine I can say this:
Never build a whole cluster fuck of mines in a small tight space for 2 reasons IF you want the mines to be Anti-Vehicle.
1. As cruzz pointed out anymore than 4-5 mines would have a negative impact on the crit chance.
2 As soon as the first mine explodes , the aoe radius will trigger ALL of the other mines, effectively wasting them as the tank in question would be out of the aoe reach.
HOWEVER. you can use these mines as an effective blob counter BELIEVE IT OR NOT. Build a large patch of mines in a small choke point where you know the herd will pass through. Either build a demo within the middle of this patch or ensure you have an AOE unit/weapon. When the herd is in the middle of the patch detonate the demo charge or throw a nade/ fire a zook with A-ground (zook is the better choice as he wont be suspicious). The mines will explode dealing decent damage all round, either killing plenty of models or if you are lucky wipes a squad.
In my opinion though, the light AT mine that the soviet AT tactics commander ( I
him) is VASTLY SUPERIOR. The mine applies a stun crit to any enemy vehicle that passes over it. That is correct, it will stun that flanking panther. This gives you plenty of time to get round the back, throw an AT nade, then a At volley and gives your AT guns plenty of time to chip away.
Note: A similar AI blob trap can be created with these mines as well.
I would of preferred if the US light AT mines gave a stun crit, as it would give your m10's the time they need to maneuver around the enemy tank as well as allowing bazooka wielding squads to hit the rear.