This one sentence shows your lack of knowledge for 2 reasons. The first reason is because have run our share of plays under center in short yardage situations. There is absolutely no team out there that ALWAYS goes under center at goal lines, other than the 3O teams that NEVER go shotgun. The second reason is because it's already been proven on numerous occasions that running the ball from the shotgun is no more detrimental than running it from under center. But don't let data or facts stand in your way, again.
And now that I think about it, I'll have to go back and check, but I believe when we scored from the goal line, we went under center for 2 plays and failed, then went from the gun on 3rd down and scored.