You have to be somehow dismissing the implications of the enormous preponderance of deleterious mutations and supposedly functionless mutations that simply snuff out alleles right and left to who-knows-what ultimate end.
no I don't, there is no reason why mutation can't give rise to both deleterious and beneficial mutations. I'm not sure what you mean by 'funtionless' mutations, do you mean silent mutations, neutral mutations or mutations which render a gene non-functional?
Yes, I know selection supposedly weeds all this out, but but that's just theory, not actual fact.
No it isn't just a theory and there is no call for selection to weed out all of what
you consider deleterious mutations, or even all deleterious mutations. It is not mere theory that embryonic lethal mutations or mutations which cause sterility will not be passed on. Less significantly deleterious mutations need not be selected out of the population, although they may tend to be.
TTFN,
WK