O2 Trim on boilers with multiple burners

I am wondering if anyone has ever done O2 trim on a parallel positioning combustion control system with dual burners.
I was think I might develop 3 seperate curves, 1 for burner A firing only, 1 for burner B firing only and 1 for both burners A&B firing.
I think the single burner control would be simple, but not too sure about duel burner O2 trim?
Any thoughts would be greatly appreciated
The number of burners makes little difference in the excess O2 control, unless you are using insitu O2 monitoring for each burner.
Have dealt with multifuel boilers (6 different streams). This complicates the startup, safety interlocks and fuel / drum level controls, but excess oxygen control for common dampers/blowers was not a problem. Good luck!
I suggest you obtain a US DOE (Dept of Energy) Document called PHAST for "Process Heating Assessment and Survey Tool". It is available from the Internet. It provides the methodology and documentation that will be helpful to you.
Regards, Phil Corso