Imagine a population of 100,000 apes or “proto-humans” ten million years ago which are all genetically alike other than for two with a “beneficial mutation”. Imagine also that this population has the human or proto-human generation cycle time of roughly 20 years.
Imagine that the beneficial mutation in question is so good, that all 99,998 other die out immediately (from jealousy), and that the pair with the beneficial mutation has 100,000 kids and thus replenishes the herd.
Imagine that this process goes on like that for ten million years, which is more than anybody claims is involved in “human evolution”. The max number of such “beneficial mutations” which could thus be substituted into the herd would be ten million divided by twenty, or 500,000 point mutations which, Remine notes, is about 1/100 of one percent of the human genome, and a miniscule fraction of the 2 to 3 percent that separates us from chimpanzees, or the half of that which separates us from neanderthals.
That basically says that even given a rate of evolutionary development which is fabulously beyond anything which is possible in the real world, starting from apes, in ten million years the best you could possibly hope for would be an ape with a slightly shorter tail.
The ONLY halfway rational argument I'd ever expect to hear would be that changes must have occurred in bunches. The problem is that if such a thing as a "beneficiial mutation(TM)" exists at all, it's hellishly rare, and the overwhelming bulk of all mutations are harmful. Therefore if mutations occur in bunches, the species will die out.
Haldane himself was a committed evolutionite and assumed he'd discovered a minor logical problem with the theory and that somebody would eventually figure out what he was looking at the wrong way, but nobody ever did. The man who has brought the topic back into vogue recently is Walter Remine. Evolosers hate it, but they don't have any real argument or case against it.
If evolution theory were true all men would be hung like John Holmes.
But seriously, evolution of mammals seem to be a step function, with a lot of "suddenly appearing" phrases in the evos literature. The evos best trick is to claim the non-evos think the earth is 5000 years old. It is their last card in the deck.