Wishing for "more power to ya!!", but your test was conducted over 1 hr and 9 minutes according to time line on your graph.
How about conducting a test for 9 days and 1 hr maybe. Just curious as to why only 105 deg? Does that not keep oxygen in the furnace water?
I hope your on to something, but cresote is nothing but trouble and it just seems that without a good hot burn cycle, it is going to accumulate. I think a smoldering fire will produce creosote, wether you steadily maintain 105 deg water or 185 deg water. The wide open burn has to work/aid in burning off accumulated creosote deposits.
Then again, suppose you were just running testing to see if furnace temp, could be maintained steady. Appears to successful, but is it conducive to clean operation of the OWB?
Keep at it, as if someone like you wasn't willing to step out on a limb, we would be less educated on what works and what don't. But, constant questioning from the likes of us on the forum shouldn't get to you. We ask questions, we will forever have "doubts", only because we/I do find it all interesting.