You do realize that in the real world most things not shielded cease to function at all after an emp. they do not just shut down and then start to work again after it passes. It destroys the electronics and everything quits. If you want reality, then here is how it would be. The enemy calls in emp. your team has no equipment for the rest of the match. Since all equipment not sheilded was destroyed and made useless scrap.
EMP shouldnt be nerfed at all or moved to Assault, putting that in support is one of the actually good things IW did with MW3, for objective players.
By doing this we who actually try to play for the objective can sacrifice a couple of deaths, but still get rewarded, and when those pesky killwhores / campers in objective games have managed to get their choppers or what ever, we can just destroy their little camping fun by turning on the EMP.
The only thing i can agree on here, is that maybe in Free for All and TDM, maybe Support shouldnt be avaible as an option, because when the gamemode is all about kills, you shouldnt be awarded for running around like a headless chicken.