45ft boat. Going up in the northern T&M locks with their vicious forward pull, I always used to try to lurk just shy of the bottom gates (being careful not get anything caught between the gates), and stay there with reverse gear. Worked-ish, but sooner or later the flow would catch the boat and once you were moving there was about 30ft in which to accelerate rapidly towards the top gates that no amount of reverse would stop. More recently I’ve tried riding the cill “plate” and gate, but provided they are good condition, and I watch the boat like a hawk. Seems to work better. Not at Red Bull though, where the cill plates have horizontal half round bars across them.