What is the relationship between feedforward control and bandwidth?
Control theory has a lot of terms that are used loosely by many people, myself included, so I'll start off with some definitions. Please correct me if I'm wrong or just talking about something different. The feedforward component of a system uses prior knowledge of the control system plus plant (output which is being controlled) to change the setpoint into the control system to get where you're going faster. So, if I have a poorly controlled oven, and I want it to hit 350 F quickly, I might set it for 400 F until I see that it is around 300, then change the setpoint to 350.

Depending on your system layout, the transfer function of the feedforward would be factored into the whole system transfer function, and therefore change the bandwidth. This can be a bit dangerous, since it can mean you are putting something with resonance in front of your component with filtration, so in real systems you need to make sure the feedforward is not going outside allowed parameters (eg I can't set my oven for 1000 F). But the theory is sound.