No such pruning occurs. D'ambricour proved that there is a mechanism that allows "chance" mutations to follow a strange attractor. Just as a tree grows branches by chance but in a coherent way because of the strange attractor, so do the "mutations". Why this strange attractor is programmed we do not know, but what it tells is that the "undesirables" should not get pruned, except in extreme cases, because they are just as capable as desirables to branch off into something better. "Nature" just does not throw the baby away with the bathwater.
Balderdash--the "strange attractor" is natural selection. The "program" is the particular "universe" of survival/anti-survival stressors that the current generation of a species is exposed to. "Nature" throws away MOST of the "babies" on a daily basis. Only a minority of species individuals born survive to breed.