I found it to be pretty challenging. The bots really do try to dive for cover... well, MOST of the time. Personally, if I were part of a 10-man squad, and I saw a heaping pile pf bodies stacked 6 deep at a doorway or corner I WOULN'T GO IN THERE.
Luckily this sort of AI behavior isn;t too common at the tougher difficulty levels- I had it happen several times where the AI bots had me pinned down and just as I was preparing to rush out and toggle slo-mo a second set of the bastiches found a way to outflank me. I loved it!