forgt subject & conf. -> evolution is NOT =math.

[Christopher L. Schardl]

Your comments seem entirely reasonable. Would you not expect that the 
degree to which this is a problem would depend on the degree of genetic 
redundancy; that is, in groups of organisms that typically have multiple 
genes for necessary functions, particularly 'bad' mutation barriers may 
be relatively easy to cross, whereas those eukaryotes (of which there 
are some) and bacteria (most) that tend to have single copies of most 
genes would very rarely be expected to cross such barriers.