Interesting discussion, and George, an interesting analysis on your blog. There was a discussion in another thread about a photographer named Thomas Hawk who is contemporary and is trying to post a million photos in his lifetime. Reactions to Hawk range from "good stuff" to he's clueless. I looked at his compositions, though, and most of them are technically quite good.
Now, I'm not comparing his work to HCB, but they have something in common. They both made/make a LOT of exposures. HCB, it's reported, would shoot as many as twenty, 36 exposure rolls in a day. When you shoot that kind of volume for years and years and years, you develop a natural sense for exposure, composition, and timing. You shoot a lot of misses at first, but the more you shoot, the better your overall product becomes. The more you shoot, the more natural good framing becomes to the point that its instinctive. There's little conscious though given to the framing and composition; more attention is paid to the subject for facial expressions, lighting etc. etc.
Now that said, a cigar is sometimes still just a cigar. HCB may have known Rouault well, and may indeed have intended to convey exactly what you've analyzed... and then again perhaps after a brief meeting, Rouault was getting ready to leave and HCB did the first shot with his hat on and asked him to take it off for the subsequent shots and the angle he shot at was what he could get... without notes or commentary from HCB, there's no way to know really.
It's interesting to conjecture though. It's always educational to look at a master's work.