Not that I want to weigh in, but I loathe the practice of changing autobrake settings on the landing roll. If PF does it, I think it's an example of extremely poor judgement and if they ask PM to do it they're forcing the non-handling pilot to look inside and move something unmonitored at a critical moment. On top of that it's not good for passenger comfort because there's a jerk from the brakes whether they're increasing or decreasing the force. 787 even has a deceleration indicator in the HUD to help you judge the braking.
If you're not capable of smoothly disconnecting the autobrake and modulating the brakes to an appropriate level manually then IMHO you shouldn't be flying a passenger aircraft. Or driving a car, frankly...