I think Mehta and the writers deserve most of the blame. It's not a particularly very well written part; the character is especially short-shifted after the tragedy. Haven't seen enough John Abraham movies but didn't think that him or any of the other cast members were a problem. Having said that, as I brought it up before elsewhere, it would've been interesting if Mehta had found a way to stick with the original script (it's not primarily her fault that she didn't), which I believe once had the great Shabana Azmi playing one of the women.