When finding players for the offensive line, are you trying to balance the players, size-wise? IOW, If your tackles were 320 (L) and 330 ® respectively, would you want the guards to be 290 (L) and 280 ®, respectively?
Depends on the scheme, but it’s more about agility than an arbitrary weight threshold. Guards typically need to be able to pull on counter plays and need to be quicker than tackles. It’s not uncommon for all 5 OL to be over 300 lbs.
Those weight were for illustration purposes only. Think of it as a seesaw-is the idea that it balance?
No. The idea is that the line protects the QB on passing plays, and opens holes for the RB on running plays. Nobody cares about “balance” in the way you’re using the term.
No, and those weights on the roster don’t mean a lot. For one thing, depending on how he carries it, a 300 pound guy can easily look and play “bigger” than a 320 pound guy. Moreover, a lot of the weights are theoretical or projected, not actual. At a place like the combine, they guys are weighed and measured precisely; but once they’re on a team, the listed weight usually stays the same even as the guys actual weight goes up and down.
Coaches care about the size of the players in order to fit their scheme, and they care about guys being in shape. Symmetry doesn’t enter into it.
Generally the tackles are taller with longer arms, the better to pass protect with. Depending on the amount of pulling they are expected to do, guards either need to be slightly smaller and good in open space, or squat and heavy for in-line blocking. Centers should be smart enough to call blocking assignments, but usually don’t have to pull, so they may not be the most nimble.
No matter what, they all should play mean and nasty.