For the sake of discussion - let's say that the evolution of mammals has slowed down, maybe even stopped (for the time being, anyway).
We are talking about large-scale, phenotypic altering macroevolution, not speciation so much.
So, granted this, the question is, so what?
Is this 'fact' supposed to prop up Davison's
entire thesis, or just the part where he 'agress with Broom'?
Or is it supposed to support ID? Or YECism? I'm not sure what the thrust of the OP is all about.