Thanks, that clears everything up
Amish coupled with polydactyly was found in my AP Bio Barrons' book.. so don't know the abstruse logistics of that but I guess you may be right.
I should've focused on the fact that genetic drift is the change in the allelic frequencies due to a chance event. Rather, I focused too much on the issue of migration of a population, which happens in the founder effect case. Any phenomenon that brings about a perceivably momentous change in allelic frequencies would have a bigger effect if the population were smaller. I think I missed that part.
Thank you for the sheep example, though OCD is a very strong term ...