I probably didnt phrase that the best....as you have seen yourself detonation can produce a variety of side effects...all pending on the root cause.

My position on your conditions is that it is not detonation. Detonation will not crack a block without significant other evidence/conditions occurring.

Number 4 chatter is a given when things are less than optimal....and that is evident in the photo....my questions where what else are you seeing in conjunction with that?