[dtw]

Someone can explain this better than me, but the way I understand it, bolts into the case place the force on the threads in the case, which it was not designed to withstand. Studs are threaded into the case, and then when a mating component (trans, head, engine mount, what have you) is placed onto the stud and sandwiched in between the case and the fastening nut, the torquing force is placed on the stud, not the case.

As mentioned previously, if you properly insert the pulled holes and then install the original stud to the correct depth with red loctite, you should be fine. You don't have to bottom the stud out in the hole. I would recommend ditching the helicoils in favor of time serts.