Calling Your Defensive Fronts

I use the same system as Coach Campbell, strong side DT followed by weakside DT. Our guys have taken to it very well, and do a good job of visualsing the front, and therefore where they should be, by the digits and name, ie 13 Under Tight/31 Over Wide etc.

Do any of you guys use wrist bands instead of huddle calls? I have seen a few coaches who send in numbers, that tell each kid where to line up via a wristband , and they say it takes the emphasis of remembering alignments and allows them to play more freely. I'm not totally convinced myself, because I expect my ILB and OLB to be able to realign a player in the wrong technique, and hence they must know the entire Defense.

Saying that, I'm always willing to learn and be shown a better way or another way. I don't know enough to say if anything is right or wrong!

Any thoughts?