Was watching a game the other day and they were doing that same inane 3 seconds of rap crap like we do when the visiting offense came up to the line. I noticed that all of the down linemen as well as the OLB all started dancing a little bit, you know, to get their pass rush on. Basically, it telegraphed who was rushing, because nobody with a coverage assignment had any time for dancing. Anyway, it would be a pretty easy way for a QB to see if a DE or OLB is dropping into coverage.