GMforPowergamers
Legend
That's called GM fiat and does not apply here. Do you see that written in the PHB? Don't bother looking because you won't find it. You can stop at level 3 if you choose to do so. You are going to have to come up with a more compelling argument than that.
How about the fact that you can make a 32nd level orc shawman, a 31st level orc grand champion (both elite) and 5 different types of Orc minnons level 25-28 and still have PCs fight them at level 28 and be challenged...
it is easier then adding 23 HD or class levels, and faster... 4e BEATS 3e in scaleing with ease....