Bypass Damper Q

[DrfluffyMD]

Thanks to mod here like BKVP I’ve been able to learn a lot about my Fabco Pioneer Z. I did some search of the forum and cant find the exact answer

The front of our baffle plate has an adjustable, removable metal plate. It does not lead directly to the flue, and during operation it can be set to wide open or flattened which make it a lot smaller.

Is this something similar to a bypass damper where it allow hot gas to circulate more and promote secondary combustion versus having the hot gas goes straight up the flue?

So far I’ve been running it open to start and closing it once fire is going

But my question is, which way lead to less cerosote? I imagine in the beginning wide open is good, but once fire is going, am I correct that closing the damper will increase efficiency and decrease cerosote?

The part I am talking about is highlighted in blue.