KidSnide
Adventurer
mneme said:So, for example, to get access to the Thievery skill and maybe some Rogue powers, you take a feat.
But to get Sneak Attack, you need to multiclass at 11th or 21st level.
I don't remember the exact reference, but there was a WotC designer blog that talked about multiclassing. He was a mid/late-heroic wizard who decided to "take the plunge" and really multiclass into fighter. My impression is that he did that before reaching 11th level, so it looks like there is some way to multiclass other than taking the abilities at level 11 or 21.
Also, the very earliest discussions of multiclassing mentioned how they wanted to let people play, for example, a fighter-wizard from the start without having to play one or the other until they got enough levels to really play their concept.
My guess is that (A) the character classes give non-power benefits at several levels and (B) the initial class benefits are broken down into bite-sized chunks with a progression. So, if you don't want to take the next benefit in your existing class you can choose to take a benefit from a second class instead.
At first level, it may be possible to take a mixture of abilities. Maybe a 1st level Warlock-Cleric gets a +1d4 curse and can only do healing word once per encounter? This would violate the "strong role" rule, but that's going to be somewhat inevitable with multiclassing.
Edit to Add: Of course, it also seems like you can use feats to dabble without losing any abilities from your primary class. I think we all know that and are talking about the "other" mechanic.