Yeah, Jillian may be tough. Personally she's too loud for me. I turn mute the TV when I do 30 Day Shred.
Some people need that though.
I also think that there was some very selective editing going on. They made a BIG deal about mean ol' Jillian coming back, so of course they're going to edit it so she comes across as super hard core and Bob & Dolvett seem sweet in comparison. After a zillion seasons of the show, I'm quite confident that all 3 of them can be very mean and all 3 can be very compassionate.