Bill, your estimate of the numbers of possible targets is off by hundreds of orders of magnitude.
As I explained before:
First, instead of proteins, consider a typical 4 base restriction enzyme recognition site. The fraction of all 4-mers that will consist of any given such site will be 1 in 256. However, essentially all 1000-mers will possess such a site; in other words, the relevant fraction is 1, as is the probability of finding such a site in a given collection of 1000-mers.
While protein function is a bit more complicated than this, the same principles apply, and these considerations cast ID proponents’ favorite probability calculations in considerably different light. Thus, as one lengthens a given set of polypeptides to lengths that approximate that required for a particular enzymatic function (and these may be rather small, or modest entities on the order of 50-100 amino acids), the fraction of polypeptides that possess a specific functional motif will reflect the size and sequence of the motif, and will decrease as the size of the motif is larger. However, once the lengths of a population of polypeptides exceeds that of a given functional motif, then the fraction of functional polypeptides in such populations actually increases with polypeptide length.
This means that all of the calculations by ID proponents that scale probability inversely with polypeptide length are wrong.