I guess you've given up on your jackknife and a steady hand.
So you move the router less than the diameter of the cutter then rock the board, or rock the board a little and move the router the length of the neck?
Kind of like rubbing your belly while you pat your head.
You're counting on the weight of the router/assembly, plus light cuts, to keep it from lifting up?
Looks like a good setup for reliable repetition.