However, the Bucs have been plagued with mediocre offensive lines since the Tony Dungy era as well. It was something that really irked Gruden, a former O-Line coach who developed good offensive lines where he’s gone. It finally appears that the Bucs are on pace to develop that good offensive line that they’ve been looking for.
I'd argue Dungy had pretty good offensive line play for most of his tenure. Gruber, Middleton, Mayberry, McDaniel, Christy and co. were good players. The Bucs rushing offense was ranked #11 in 1997, #4 in 1998, #15 in 1999, and #9 in 2000. But just about all those guys were gone by 2001 and replacements like Walker and Colemen flopped and the unit sucked from then on.
The rest of your analysis is solid.