So, a few things here.
As awesome as it would be there isn't really an option to do an "if/then/else" with the SethMods-Mini code.
So you can't say
If LT pulled then do Jitter Else do Rapid Fire.
The best that you can do is a "do/while" loop. ...which is what the "Wait RT Pull" does.
Also, the first line "User RT Pull" is the same as "Wait until RT Press".
So essentially your code reads...
Wait until RT and LT are Pressed
Fire one shot
XXY
Loop
So to get "Jitter" to work you have to pull both RT and LT. Otherwise it gets hung up in one of those two waits if EITHER is not pulled.
Now you could essentially do kind of like a LT Cancel (except backwards) where if both triggers aren't pulled then it isn't going to jitter. But it isn't going to rapid fire.