[VadeRetro]

Now the critical time for a neutral and even a beneficial mutation is the start i.e. when very few individuals carry it but once again, this doesn't mean they have to disappear.

While computer models show that the average neutral mutation dies out according to a certain formula, the usual bell curve applies. About half the cases do better than average, and some cases do two standard deviations better. You're right, pass a certain threshold of success and you don't die out unless perhaps your whole species takes a big hit. Meanwhile, new neutral mutations are always occurring.

So what you see when you sample a sexual species is a swarm of alleles for most genes being combined and recombined in unique individuals. Because of all the variation to select from, it's a situation ripe for evolution.

[BMCDA]

While computer models show that the average neutral mutation dies out according to a certain formula, the usual bell curve applies.

The blind drunkard in a corridor ;)
Will he return to the wall he just lost contact with or will he stagger around until he hits the opposite one?