I am really, truly, sincerely doubting that Google cares about what SEO's think are "competititve keywords".
I'm also kinda doubting that there's a good metric for "competitivie". Some phrases aren't competititve, they're just popular. What's Google going to do, knock down any widgets page that happens to mention George Bush? That would be weird (and hugely disappointing to any widget company that gets endorsed by George Bush).
Anyway, what is a thread of complete guesses to accomplish, besides creating more urban legends and misinformed newbies?