If the main goal is to get to the national championship game (not win the ACC), theoretically I would take not making the ACCG assuming we get the 5 seed. You play the same amount of games, open up the playoffs with the 12 seed at home (which will be a team worse than Clemson, the most likely ACCCG opponent), and then play a quarter finals game against the 4 seed which is likely to be the Big 12 winner (Iowa state or K state). That will be a game we are favored in to get to the semifinals.
If we play the ACCCG, even assuming we win and get the bye, there will be a tougher opponent in the quarterfinals as the 3 seed to get to the semis.