Thanks SmokinJohn - yes, all input helps! I am going to do some more tests and try and avoid getting my head around the quantum physics of inlet/exhaust load-balancing, or whatever it is, and try the KISS method instead!
To date, I have only had the 2" exhaust open, and generally the inlets closed, and the ball-valve marginally closed. I am going to see what the impact of opening other exhausts are, assuming inlets stay the same.
-Wood Fired Pizza Oven - Brazilian 'Churrasqueira' -Apolo Plus Esmaltada BBQ - Classic UDS -