You obviously have more time to watch clips and film than I do but that doesn't seem like a sweet release to these amateur eyes. His last two steps before he accelerates downfield look fairly slow and deliberate to me. He seems to get open because Griffin doesn't lay a hand on him at the line and then can't make up the extra step because of Metcalf's 4.33 speed (despite Griffen's own elite speed).
Well let me help you out ...
DK uses a motor release at the line. That's designed to "reset" the los, often inviting contact bc of the shutter/staggered footwork. DB's react and see a target but if you look or are familiar with it. You'll see his arms in motion which is designed to beat contact with chops/clubs etc ... Which DK is vg at. He was really good at beating press with various releases and getting physical.
So if you jam and miss or it isn't effective, you're done.
He actually gains decent separation off that initial release if you slow it down or stop it frame by frame. That's not bad at all and you're ignoring the obviously here. DK is a monster at 6'4/230, those are great movement skills off the line.
Anyway he doesn't stretch but just goes into a speed release and at one point. Again slow it down or frame it. He's leaving Griff if that ball isn't under thrown.
Neither WR or CB were getting physical during that drill. At the line or catch point. You see them give about 75%/80% at the line and Griff almost tagged him to keep DK "upright", which you'll hear coaches say all the time.
Again most impressive thing there was the stem/stack by DK. That's a big play if the ball isn't under thrown.
Plus another thing people fall to remember when watching a lot of these clips on deep shots. There's no S over the top so again a lot of highlights on Twitter are incomplete in live action.
Play vs Cal is very similar. Looks like a motor into a speed release. Inside stem, shakes contact, stakes and he's gone.
