I dunno what the issue is with having multiple land mines in close proximity, it makes for a bigger boom and will kill a tank dead on the spot if a driver is careless & doesn't spot them, that's the whole point of a land mine, to kill a tank DEADS, not just partial damage and then allow the tank crew to simply stop & instantly repair the damage from 1 mine.
Armor will always dominate the battlefield, that's why I play AT/Engineer since BF2.
They just fixed the exploit where you could have them in close proxy which I thought was petty to fix that.