Ichneumon can post his own response, but I'll give you Darwin's view of it, and he knew nothing about genetics. This is from Origin of Species (6th ed.), Chapter 2 - Variation Under Nature:
The many slight differences which appear in the offspring from the same parents, or which it may be presumed have thus arisen, from being observed in the individuals of the same species inhabiting the same confined locality, may be called individual differences. No one supposes that all the individuals of the same species are cast in the same actual mould. These individual differences are of the highest importance for us, for they are often inherited, as must be familiar to every one; and they thus afford materials for natural selection to act on and accumulate, in the same manner as man accumulates in any given direction individual differences in his domesticated productions.Variation and natural selection. That was Darwin's theory.
I think Darwin would agree with me. ( :-D