The point of view I hear, whenever I read old grouchy people insisting on a technical interview, is that if you don't have one, you'll end up hiring somebody that can sound smart when talking in a conversation but can't actually do the job. I've never actually encountered an old developer of respectable ability that is in favor of omitting technical interviews.

You say you want to know how fast a candidate learns. If somebody can't solve trivial programming problems, what does that say about how well they learn?