> I suspect however, that the effect of not quite perfect burn schedule and burn intensity of the propellant has a much greater effect. This is the real answe

> I suspect however, that the effect of not quite perfect burn schedule and burn intensity of the propellant has a much greater effect. This is the real answer right here. Rockets have all sorts of uncertainties in them. You have the measurement uncertainty in exact orientation and the measurement uncertainty in the acceleration and thus total thrust delivered, all on top of the physical uncertainty in exactly how powerfully your engine is going to burn, and for how long. Remember, there are physical valves that need to open and close to control propellant flow, and there are chaotic perturbations in the conditions inside the combustion chamber. You simply cannot remotely achieve a perfect delta-v in a perfectly specified direction; there are uncertainties on both.