I never said that it by itself invalidates the theory altogether :) If someone puts a theory forward, however, it's their job to come up with plausible answers

I never said that it by itself invalidates the theory altogether :) If someone puts a theory forward, however, it's their job to come up with plausible answers for such doubts. The one you suggested is possible, of course. How well substantiated it is though? Theories should include some evidence that supports the hypotheses they are based on.