Twiddle, AKA coordinate ascent, definitely works in practice. It's basically the same process a human uses to tune PID parameters, cyclically tune one parameter

Twiddle, AKA coordinate ascent, definitely works in practice. It's basically the same process a human uses to tune PID parameters, cyclically tune one parameter at a time until you're performance is good enough. It's closely related to gradient ascent and suffers from the same problems, namely that it can get trapped in a local minimum, but it's easy to implement and does a good job if you start with an ok guess at the parameters.