Harshness of engagement..... That is the support strap I referred to and which I broke on a PP once upon a time. Revved high and dumped hard on pavement. Instant vibration. Never did that again and never bent/broke any of those straps again.
Each such strap has a limit; I broke that one with just a modified 130 HP Opel 1.9L Engine. If you rev and dump on pavement, then the springs in the disc get 100% compressed and the remaining shock goes elsewhere; something like this will happen sooner or later.
Glad it was that easy IM.