Here's where I'm confused Dave. An oven is essentially the same thing. Cooking chicken in a 350 degree oven, the box temp is 350. It's, like the smoker, not a sustained 350. It swings back and forth; and the meat temp never gets to 350.
So, 225 in the smoker is the same as 225 in the oven. It's all box temp. In the oven, I can't get the water pan as close to the heat source as I can in the smoker, also, the source of the heat in my oven is more spread out. My buddy does his in the oven, so I know that it'd work, but I can't really see the downside/disadvantage of doing it in the smoker. Like you say, 225 is 225. If water will create steam in a 225 oven, it should create steam in the smoker, especially with a smaller footprint on the heat source.
In any case, I'll try it, most likely with an empty box first, and report back.