The loop itself doesn't collapse, but the P07 piece is different than the P09 piece. It is shorter and slotted deeper and as you "lean on it" to push the hammer spring up into the frame it tries to bend at the bottom of that slot and cut where the pin passes through it.
I may eventually order a P09 piece and see if I can shorten it, but not slot it all the way to the pin holes.
I've only installed mine twice. Once when I got it and again a few weeks back when I had it apart to do some polishing and installation of the CGW reduced power springs on the trigger return and the firing pin block spring.