Interesting to hear your experience. I ran some light Trail Boss loads in .45 Auto at one point and was astonished by how cleanly it burned in them. Not even any soot or blackening inside the cases. They looked like they'd just come out of the tumbler. Way better than Bullseye does for me. However, that was with a very heavy bullet of my own design, which would have helped it burn better.
The problem with burn rate charts is they include a lot of guesswork. A Hodgdon tech told me the burn rate test is expensive to have a lab do, so they don't pay to have it done to competitor's powders, especially since you can't know from one purchased sample to the next how close to their target value they are. All the distributors consider their in-house numbers to be proprietary, so they aren't sharing the information, either. Additionally, the exact order can flip around under other pressure conditions than are present in the standard test. I always think the charts that group powders together by application have a more realistic perspective on the whole thing.
TB is, as you say, positioned down from Bullseye, but its above 231/HP38 which is used in most of the same kinds of loads Bullseye is used in. So these guys are all sharing a ballpark. All faster than, say, Unique. All slower than Clays or N310, or the several other very fast powders out there.