So will the Pouncey Twins
They'll make a difference, but honestly, that line didn't perform well this year....they gave up 28 sacks, which was 10th in the SEC, 70th in the country. (Tennessee and Georgia led the SEC, only giving up 12, Auburn only gave up 18).
You're right, they'll be missed, because of their experience and leadership and things like that, but as far as straight up numbers, I would think new members of the line could probably perform as well as this years line.
Separate note, LSU gave up 35 sacks this year, good for #107 nationally. Holy shit that's bad.