I think that programmer knowledge has a short half-life, but not so much programmer skill. I agree that programming well in language X and programming well in l

I think that programmer knowledge has a short half-life, but not so much programmer skill. I agree that programming well in language X and programming well in language Y are very similar (unless perhaps X and Y use radically different paradigms), because programming well is a skill. But there is language specific knowledge you need to pick up; it's just relatively fast to learn and you can bridge the gap with references.