The Down Belly has been a big part of our Wingbone attack over the years. Following are blocking rules and key coaching points :
TE Gap-Down-Backer. (If the FST is uncovered, TE takes 5 foot split and takes "easiest" release to LB)
(Also, you could have TE reduce his split and make the 7 technique a 5 technique. Now block down
the 5 tech and FSG trap the OLB).
FSG Pull & trap 1st defender from "C" gap out.
FSHB Influence EMLOS and wall-off PSLB. Get hat in front of the PSLB and you must get to him before he
gets to the FB. (Your path is outside the DE).
Coaching Point : If the FST is covered, the FB tracks at the inside leg of normal TE and must hug his (TE)
down block. If FST is uncovered, FB tracks at tail of FST and now hugs the down block
of the FST.
Hope this helps,
In the wing-t, the belly/belly option steps for your qb are "45 & deep". For the down/down option your qb steps are "flat & fast". This times up well with your fullbacks steps on belly/belly option which is "lead/cross-over" and on the down/down option which is "straight to point of attack. Hope this helps.
I always tell our FB to aim for the outside leg of the PST. It's got to be repped and repped and repped. The down has been a staple in my offense for the last 3-4 years. So, I'm familiar with some of your concerns. Sometimes in Offensive Indy's, you either need to lay out some cones or spacing boards to get the FB where you want him.
We use a 3/4 Inch 10 foot long piece of PVC Pipe running on air.......Make him run the Path and not look at the QB for the Hand off, As soon as he looks for the hand off he'll move into the B Gap. I will stand at the LOS and Hold a 2" piece of 10 foot PVC pipe at my chest height to make him run low....After he gets his path down add the QB hand Off....After that you give him a direction to cut by Flashing a finger pointing inside or outside at the exact time of the hand off...Watch the FB's eyes....