"eliminating the weak from the gene pool will result in a healthier population"
Sorry to say, but this is incorrect.
It should be:"eliminating the weak from the gene pool will result in a healthier population
under current circumstances".
The difference is incredibly important to evolution and genetic variation (even the seemingly weak ones) is a big part of the survival mechanism of a species.
It is, as we have found out in biology over the past decennia, the core flaw with the eugenic line of thought.
It's difficult to figure out who exactly is weak, too. You'd think if you wanted strong people, you'd pick football jocks, but...