puzzling over formations - question for coders

[MiRai]

I figured I would turn on click to move and post WM_RBUTTONDOWN and WM_RBUTTONUP to the slave, with client coords corresponding to the click position in the master window.

That's against the rules of the game.

I am thinking of sending an automated stream instead, such as turn, turn, turn , start autorun, wait, stop autorun. Would that break Blizz ToS though?

That's against the rules of the game.

Any coders out there have any idea how the pros do this?

The "pros" do it the same as everyone else: They press and hold down keys tied to movement to move their characters, and release the keys when they wish for their characters to stop moving.