Let's talk about Clemsons sterling D against three "powerhouse" teams...
They suck... If there D was any good Louisville wouldn't have been able to score.
Their efficiency rating was as high as Clemson's offense. They had fewer first down (4 less) but they ran fewer plays.
They won the turnover battle.
They had more passing yards on Offense.
The point is - The taters D sucks and you shouldn't be giving them any credit.
And they were only adequate enough against Louisville.
Had Petrino used the final 4 minutes correctly they could have kicked a tying field goal and then who knows what happens. Such is life, however their Defense (if it was so stellar) never should have allowed Louisville to even be in this game.
You'll see when ND comes to town and set you Taters straight.