Juju may not be the fastest or have the best separation speed but he does everything else really well, route running, blocking, combat catches....
Jerry Rice was slow.
Larry Fitzgerald is slow.
JuJu Smith-Schister is slow.
I guess that I don’t mind slow.
Davante Adams and Juju are similar in size and forty time.
Adams has a better broad jump and vertical, plus he ran a 3 cone and Juju did not. Although I did find some reports that Juju was under 7 seconds at his pro day in a 3 cone.
https://nflcombineresults.com/playerpage.php?i=22492
https://nflcombineresults.com/player...=Adams&i=20912
What is my rambling point? Juju is plenty fast and quick enough for his size to create the needed separation to be open in the NFL. What he may need to still refine is his route running and using technique to get even more separation. That is what Adams learned and perfected his first 3-4 years in the league. He also benefited from other WRs in the GB offense (Jennings, Nelson, etc) early in his career. And then he exploded as the #1 WR in the offense and became one of those WRs that is always open.
And basically he has the same physical skill set and body size as Juju. So...Juju is more than fast enough....but is he technically proficient enough? That remains to be seen. The biggest reason to run Juju out of the slot is that allows him a clean break off the line. That is one of the improvements Juju needs to make to his game. Be able to get off the LOS from any of the WR spots. Same with Claypool. The best get off is Johnson -- which is why he plays AB's old spot.
Flat 40-Time is nice but you rarely run a straight 40 in football. I look more at the 3-Cone and the Shuttle run and the 40-Time as a supplement to those. That start and stop/acceleration is more important most of the time than flat out speed.
Also, as a DB (or WR) you may run a little faster if your chasing someone...or being chased...lol.