Unfortunately, a site I really respect, Swim Smooth, recommends avoiding glide, though I do think that a good 80% of the swimmers I see could do with extending the reach of and calming down their front crawl stroke at least some. Bottom line — not too much glide and avoid dead spots.
Swimming is awesome. It seems so simple, but there’s always so much to learn. (disclosure: I’m surely an overglider)
Also see, rotate your elbow, not your hand.