According to Blizzard's RAF FAQ, for every RAF account character, you are allowed 1 level to grant per 2 levels on the character...

If you are running 2 RAF accounts with 1 main account:

1st group of three to 60: 30 levels per RAF account to return/grant to main account (60 total)

2nd group of three to 60: Additional 30 levels per RAF account to return/grant to main account (60 total)

It's not limited to the first character created. Theoretically, if within the 90 day window you run 2 groups of 3 to 60, that would give you 120 levels to grant back to your main account, or basically 2 free 60s. My suggestion, don't grant 'em to melee characters, leveling up your weapons skill from 1 to 300 has to be a beeeetch...

So to answer your question, yes, if you run 2 teams (using 1 main and 1 RAF account) to 60 then each RAF toon has 30 levels to grant to your main account, but you'd only use 59 of them since you can't get past 60 using RAF granted levels.

As an aside, in 90 minutes last night using the RAF stuff, I got a group of 3 (see sig) to level 12 with about half of Elwynn Forest still left to complete. Pretty slick.