After reading about how experience works...
 

Makes me wonder, what is the most efficient lvl combination for my bard friend and me (rog) to be lvling together? he is lvl32 and I am 37 right now. He is going to close the gap some before we get a chance to play together again. I won't go way out of our way to get these ideal levels, just curious.

It is my understanding that total experience would make his lvl32 bard similar to my lvl37 rog?

Exp penalty is shared in groups, so you would level at the exact same speed if you were both level 37.

While you are correct that total xp needed to level for a 32 bard is similar to a 37 rogue, that point is mostly irrelevant in a duo situation.

http://rantsandflames.com/xpcalc.php