Yeah, guards matter very little. The only thing they do is block the interior defensive linemen who have the shortest route to the QB. Well, they also have to keep the pocket clean so the QB can step up into his passes. On top of those things, they have to open up running lanes for the RB to run through. Additionally, they often have to pull to get out in front of a sweep or swing pass/screen. Then, of course, they must be able to read the defense and adjust their blocking accordingly to account for a blitz or stunts. But other than those things, I mean, yeah, guards matter very little to the success of the offense.