I think you are really underestimating the role of injuries this year. There was a post in another thread that showed that the main difference between this year and last was the performance of the O; the D was about the same, but on the field a lot longer this year. Why?
You've hit on it yourself. The main difference between this year's team and last year's was the decimation of our skill players on O. I posted on this before, but of the two-deep of skill players we expected to have on the field at the start of fall practice, we had a grand total of two on the field this year - JT and Ike Willis. Even the new kids we were expecting to help - Cotrell and Benson - got hurt in the fall. Then Snoddy and Searcy went down. Iow, we not only lost our experienced skill players before the season, but we had to change the cast of characters during the season as well, moving MLD and Jordan to AB, then moving Jordan back to QB, then shifting the OL because of Shamire's concussion, then … you get the point. The result was there for everyone to see, especially in the games we played in the slop with new kids all over the place.
And, btw, we lost both Leggett and Quaid in the spring. That's why we jumped at Skov and moved Allen. That really hurt, for reasons already pointed out here.