I sort of agree with you on lethals, but I know there are people that rely on them heavily, especially C4. I can't seem to get the hang of using C4 as a thrown explosive.
Anyway, I definitely have to disagree on EMP's though. They're probably the most useful tac., and pretty much the only grenade I'll use. --- If it's true that we learn from our mistakes, then I should be a frickin' genius by now.