It sounds like you have don't know too much about playing on the line. One reason a lineman will come out of the stance slowly is that he is unsure of his blocking responsibilities. For example, let's say the defense is stunting up front. You know what happens if you fire off the line and try to hit the man in front of you? You are going to be blocking air. On the flip side, if an OT thinks a stunt is coming and doesn't understand his responsibilities, you might see him shuffling backwards to try and buy more time to identify his rusher and also so he doesn't get blasted by the DT coming from his right or left. Let's say an OT know 100% a stunt is coming. It's a disaster if he tries to reach and block down at the exact same time the guard is trying to block the DE coming around (or crossing in front). The result will be running into each other and taking both the OT and OG out of the play. If the OT thinks a blitz is coming from the outside and doesn't have help (or doesn't realize he has help) he will often try to block two guys at once and fail. Or he'll pick the wrong guy. Again, pre-snap he's thinking too much and not moving with instinct, which makes him a step slow. But as anyone who has played on the line will tell you- the #1 reason that a player is slow out of his stance has to do with snap count. You think it's easy, but there is a reason that even in the pros, you see false starts all the time. An OLineman wants to hit his guy first as soon as ball moves a nanometer. It takes a lot of practice (and sometimes lots of gassers) to get an OL with a habit of false starts to stop jumping, but on the flip side it can make him slower coming out of the snap. There are lots of things that can be easily fixed with experience and a more player-friendly scheme.