You can laugh all you want but you clearly don't watch much football. Mario Williams played OLB for the texans before he came to buffalo, making the switch from a DE - i believe he had something like 6 sacks in 5 games before going down with an injury.
And you dismiss Dareus and his sacks from last season as nothing, but he was more dominant lining up in the 3-4 last season than he was this year in the 4-3..whether you want to blame this season on his brother's death or the change in scheme i dunno, but the fact remains: Mario, Anderson, Dareus, KW have ALL played in a 3-4 and been SUCCESSFUL.