i have read many posts about the mgs and ATguns units.. if you want the unit to retreat, then it will be immortal! for example: the arty is comming and you retreat the unit, then you come back and nothing happend (exept for the AT gun, wich has minor damage). as same is for snipers.. if sniper come,the only thing to do will be just retreating the crew of the stanionary weapon. in my opinion, if that would be possable, it would just ruin coh.