I've worked out, that a rich fuel mixture, i.e., unburnt metals leaving slag, will achieve best ratio as additional air is scooped in and injected into exhaust plume.
All 4 injectors, always open.
Even (if) the rocket pitches\yaws, pressure builds on that side, inducing even more air through it's corresponding injector, (on opposite side of injector) it'll cause no additional increase in thrust performance, but, was in fluidic thrust vectoring, it'll "push" the flow of exhaust gasses towards opposite side, resulting in correction of errant pitch\yaw.
My deliberation now, is whether or not there's still "extra meals" at that point...
Tough problem 2 solve.
As the speed increases, and air pressure drops, I figure approximately static effect on fuel\oxidizer ratio... Approx. Only counts in horseshoes and hand grenades... definitely not here.
I am trying, here on Earth, but that, isn't even close to actual conditions.
Ahh, just came 2 me...
Motor grains with increasing (or decreasing) amounts of extra metals to account 4 the changes.