Hey Control Freak.
Unfortunately I do not agree 100% with your statement. I believe that a bypass will HELP prevent smoke roll out but not eliminate it. Smoke roll out depends on a few factors such as draft, stage of burning, proximity of the wood to your door, etc. If you have a bad draft and a piece of wood against your glass, it's almost certain that you will get smoke outside. I have a bypass on my current stove and it helps. This link also stipulates a good point:
http://woodheat.org/woodpile/index....gram&catid=20:emissions-regulations&Itemid=10
"
catalytic stoves (by far the majority) have a baffle that occupies the whole top of the firebox except for a
narrow slot just above and behind the door. This slot is only about 1 1/2 inches wide and forces the exhaust to exit the top front of the firebox and then travel back through a flat chamber above the baffle to the flue collar where it leaves the stove. This works fine when the door is closed, but when it is opened to put more wood on the fire, the exhaust can spill out the top of the door opening if it isn’t all drawn through the narrow exhaust slot. The only thing to prevent open-door smoke spillage is very strong chimney draft, which is produced by tall chimneys that ideally run straight up from the stove flue collar. Lots of homeowners don’t have chimneys that produce enough draft to prevent smoke spillage, given the obstacles created by advanced non-catalytic combustion systems."
A bypass does help, there's no doubt about it. BUt it's not the 100% solution. And I do agree, don't open with a yellow flame, wait until you only have coals.
Andrew