Originally posted by Theo Wizzago
Actually? No. I've used it very seldom, but with my own builds I never saw a difference. Sometimes I think what you see in the videos doesn't reflect what many think is that 'jump back' based off of 1st step. Both O and D linemen have abilities to 'shunt' a dot... either aside or backwards. Plus there are interaction rolls where one dot is trying to pancake/revcake it's opposite number... loses the roll... but makes a 'balance save' which has the exact same look as a dot 'jumping back/aside'. Since there's no info bubbles to let you know when that occurs you're left to guess. I recently watched one of my DT's shove a poor ol' Center aside several times in a game, flattening the QB before he ever had a chance to even read his 1st progression (I know because it was my poor QB he was flattening!). For all intents and purposes someone might think the Center had 1st step but he didn't... but it sure looked like he was 'jumping back/aside'.
I do get it though that it could cause the same result as one of those 'shunt' maneuvers... or a failed 'cake/revcake' but passed the 'balance' save. All in all, I just say this... there are better uses for SP's and other good SA's out there that I would get before 1st step for any O-lineman. 
I've always been skeptical of the supposed "OT first step curse" but I've never used it myself. Basically, I don't think it is that useful for OT since they don't have to pull as far as the Guards so I haven't used it- plus I was afraid of the glitch everyone talks about. Now, however, I'm guessing its probably not a really a thing per se. I'm guessing its more to do with the OT not being agile enough to handle the DEs speed, and like you said, he lost a roll, I'm guessing its usually one that allows the DE to cut back to the inside- and it just looks worse visually because of the Fist Step, but the exact same thing would have happened with or without first step. When the CB over runs the WR as the WR makes his break, is it because the CB has first step? No its because the CB lost the roll to cut when he needed to. I'm guessing that is really what is happening with the OTs and the First Step only makes it look worse.
First step is actually great for Guards though, especially if you use pulling Guards, which you really should if you want to run outside the tackles. Also it greatly increases their push off the snap, because of how GLB measures velocity (mass times speed travelling plus strength, more or less) and because of that, though you can't see it- they are actually travelling faster in the tiny space between the snap and when they hit the D-lineman, and that extra speed means extra velocity which means more power. Now its not like it'll make them hit twice as hard, but its still makes a positive difference at something they do every time you run the ball.