You'd do well to read Ichneumon's post on this subject again, this time for comprehension. Your hypothesis bespeaks multiple incomprehensions on your part, so many that it seems unlikely that you have made any effort to understand how populations evolve. You think you've got your "gotcha" that somehow 99% of PhD biologists haven't spotted, and you don't want to let go of it. Fine. Here's a hint though; Mendelian genetics has enormously strengthened evolution, not weakened it. In Darwin's time genetics wasn't known and it was a serious potential weakness of the theory that no-one knew why beneficial differences between offspring and parent didn't just dilute through the population as time went on. Genetics explains the lack of dilution.
This is one of the sillier aspects of the creationist mindset; that you/they spot an objection to mainstream science that a 10 year old could understand, and they think therefore that they've found something that invalidates multiple scientific fields of endeavour that hundreds of thousands of people spend their working lives studying. Presumably you think that either (a) all professional biologists are stupid or (b) all professional biologists are knowingly engaged in an atheist conspiracy to destroy Christianity or (c) both (a) and (b). If you are a young-earth-creationist you can extend that to "all scientists are fools or liars or lying fools".
>You think you've got your "gotcha" that somehow 99% of PhD biologists haven't spotted, and you don't want to let go of it.
You're damn right I do.
And I noticed that you have to spin away from addressing the math.
It's not complicated, a kid could figure it out.