If you've read many of my rants or attended any of my presentations, you've probably heard me address "rules that aren't" -- those little superstitions have become the public face of grammardom even though they have little or no basis in fact. Split infinitives? They're just fine, and often preferable to the alternative. Ending sentences with prepositions? Beginning sentences with conjunctions? Nothing inherently wrong with either practice.
But I'm far from being entirely descriptivist. There are plenty of very common usage habits that have to be called inadvisable or just plain wrong, even when they produce perfectly understandable sentences. One such no-no is the dangler. I sometimes draw a blank when I have to come up with an example of a dangler, but I came across a couple of them in quick succession as I started to read the autobiography of Muhammad Ali's trainer, Angelo Dundee, and I thought I'd share.
Unable to renew his unrenewable youth, Ali's skills had declined during his enforced layoff.It was Ali who was unable to renew his unrenewable youth, not "Ali's skills." Recast.
Awkward and rugged, it seemed as if Ali had underestimated him and his strength.It was "him" (opponent Oscar Bonavena) who was awkward and rugged, not "it." Recast.