I remember it stinks when you cut it. Don't know if it stinks after curing.
Never noticed that, but elm stinks when you cut it. That's probably what you're thinking of.
I cut a lot of cottonwood for firewood, because we have 40 acres of southern Colorado river bottom and lots of dead trees from the drought. I use cottonwood because: A) That's what we have. Hardwoods aren't exactly in abundance in Colorado, and B) It actually burns cleanly and quite well. A couple of splits will last an hour or so in the wood stove. The rare hardwoods we get are Siberian elm (not so good) and Mulberry, Ash, or Black Locust (very good, but rare). The hardwoods are for "overnighters" here.
My theory is that the cottonwoods here grow slowly and more dense because of the elevation. I have trees at least 120 years old on the place. And, I recently found out, you can actually use cottonwood for meat smoking. The taste is pretty good.