I wanted to write about this the moment I saw the play.  This was a nearly perfect execution of a double move and deep ball combo that you can expect, and a very good example of what speed in space means for this team.  

First down from the Michigan 13 yard line.  The team is lined up in a 12 Personal Package with both tight ends lined up on the wide side of the field  Johnson is at the short/bottom of the formation just inside the numbers and I believe it is Roman Wilson on the wide side.  the TE are All and Horningford.

After the snap McNamara drops back and it is a 3 man route.  All runs a crossing route about 10 yards deep.  Both Wilson and Johnson are running a 10 yard curl and go double move.  Wilson does not sell his curl well and it almost looks more like a simple go route.  Johnson however does a wonderful job selling the shorter route, forcing the defender to make a decision and then blowing buy him in a matter of 3 steps.  For this to be successful you need 3 things to happen. 1) the WR has to sell the first move as his primary route 2) the QB has to be able to either sell that first route move with a fake or sell that another receiver is the primary and keep the single high safety off of his intended receiver to keep it a 1 on 1 route.  McNamara does the second,   watch his eyes he is focused on the TE (All) running the middle cross, all the while Johnson has pushed up into the DB's space and widened his route to at the numbers, allowing the DB to think some sort of out route being run.

So now all three receivers are supposedly at the top of their routes, and you can see All has put his foot into the ground to cut and Johnson has thrown on the breaks to the point where the DB has nearly overrun his coverage.  All this time Cade is looking at the TE over the middle, the deep safety has started to converge on the TE as well.  The final piece of this play and it's success is Blake Corum stepping up into the hole and stopping the blitzing LB cold which give McNamara time to change targets and make the pass.

From this point it is academic Johnson has his cover man in conflict with no help over the top, McNamara has a nearly perfect pocket, and all that is needed is a nice clean pass for Johnson to catch and take to the house. 

This is a split second after the previous field shot and you can see that the DB is still breaking down to cut and Johnson has already planted his back foot in the ground and is transitioning back downfield.

Now Johnson and the DB from the endzone.

Johnson throws on the breaks, look at how the DB is trying to stay on top so he can make a play on the ball

Johnson selling the curl route including the head turn and see the DB follow

Oh Shit not a Curl route.... the DB has stopped and Johnson is now ever with the DB and you all know that when the WR is even with the DB the DB is in trouble.

Three steps later and Johnson has space and nothing but clear sailing and a ball to catch.

finally the catch, Johnson has 3 yards on the nearest defender and the ball was a well thrown ball that was easy to catch and stay in stride.

https://youtu.be/1Z9XlKVKaTQ