I'll take him just the way he is....except with a bit more focused defense.
FWIW, Teague's game 3 highlights were up on youtube. He made 9 shots, Rondo was only guarding him on 2 of them. I still don't see how that amounts to awful defense.
Its the way he plays off his man and allows him to shoot open shots, penetrate and create and get out of position for rotational defense.
Rondo wasn't playing solely on Teague that night and his poor defense wasn't resulting in just Teague scoring. Often his man gets by him leading to a rotation from the big men and leaves a man underneath wide open for a pass from Rondo's man. Or because another guy rotates it leads to someone else wide open and Rondo way out of position to help on that player.
Rondo also has left his man wide open for many, many wide open looks which have been missed. If he was guarding a shooter like JJ Reddick or Kobe or Rip Hamilton or Rose, those guys would be constantly scoring big.
Listen, I love the guy but be objective here BBall. He plays way off his guys to play the passing lanes. He leaves his guys wide open for shots and his guy often blows by him leaving the big men to try to pick up his mistake. This often leads to layups or dish offs for layups dish outs for open shots. When he loses the ball offensively the first thing he does is complain to a ref instead of getting back on transition defense. His rotations are the slowest on the team and he's the fastest guy on the team.
I love him but I loved his defense from 3-4 years ago better when he was a more in your face, stuck to your man defender and not this roaming safety type defensive player he has become.