Or replace some unneeded general skill with "basic mine protection /mine-jumper" A single mine then does always less then 70 HP damage against an Infantryman with that skill and launches him 3 meters into the air when he steps on a mine (including particle effect for "rocket"-jump). Multiple mines should still instakill you.
Bah... that is too silly to even consider it a possibility although, the same might be said about scout hide.
There are two ways you can do that. drive an APC over it and depending on how high it jumps you know the number of mines. (no i dont have a formula for # of mines to airtime/altitude.) 2.) you find a mine under the mine you just defused.