Buffalos and Braincells - Just a Coincidence?

I have not seen anyone explain it as well as the all-knowing Cliff Clavin,
on the sitcom Cheers. One afternoon at Cheers, Cliff Clavin was explaining
the Buffalo Theory to his buddy Norm. And here's how it went:

Well ya see Norm, it's like this...A herd of buffalo can only move as fast
as the slowest buffalo. And when the herd is hunted, it is the slowest and
weakest ones at the back that are killed first. This natural selection is
good for the herd as a whole, because the general speed and health of the
whole group keeps improving by the regular killing of the weakest members.

In much the same way, the human brain can only operate as   fast as the
slowest brain cells. Excessive intake of alcohol, as we all know, kills
brain cells, but naturally it attacks the slowest and weakest brain cells
first.  In this way, regular consumption of beer eliminates the weaker brain
cells, making the brain a faster and more efficient machine. That's why we
always feel smarter after a few beers.