That is correct. They do not create loads of creosote on super low burns. For full disclosure, here is what I have gathered, putting roughly 50 cords thru my own two BK's and reading way too much on this forum:
1. BK's are usually run at much lower exhaust temperature than most other stoves. This is probably due to the combination of two factors, (1) very high efficiency = very little heat up the flue, (2) folks buy them with the intent to run them very low for long burn times.
2. This low exhaust temperature increases the likelihood of the particulate matter that does pass thru the combustor actually condensing before it reaches the top of the flue. So while all EPA stoves have some particulate output, that from the BK may be more likely to condense, due to the lower exhaust temperature.
3. Most cat stoves work by burning in bypass mode for 20'ish minutes on a cold start, waiting to get the combustor up to temperature. During this period the flue is cold and particulate output is high, so expect some deposits.
All of this adds up to BK's probably having higher creosote deposits than many non-cats. But even stating all of that, it is a non-issue for most of us, especially when compared to the absolutely filthy pre-EPA stoves many have run. Most BK owners still only need to clean their flue once per year, like most non-cat burners, but they will probably get more out of the flue when they do.