Contain assignments are already built into the schemes in M25 albeit they do not play out that way but by the looks of things: in M15 the mush rush will now animate for those said schemes that have *contain assignments by default.
If you look at the play art for the cover 2 zone QB contain in Shop's vid: you will see two DTs fire and the two end's come in on angled routes so as to collapse on the edge - this edge assignment will now be animated as a mush rush when a QB contain play is selected.
Adding customizable blitzes to these mush rush contains will be interesting and add to it the user control to call your own dynamic mush rush contain from within any scheme and we get what they were spelling out in respect to more user control on D.
On a sidenote, I saw a vid from Cullenburger that revealed the tackle cone on a KR and the return man was able to elude the defender because the defender committed to his aggressive tackle while the return man was outside of his cone - this led to a whiff animation.
I am looking forward to a feature on the tackle cone because it seems heat-seeker is toned down or removed totally which I would appreciate as it will alleviate the prevelance of warp tackles and the spamming of dive tackles.
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