If a rider has his cleats set all the way back, it require you to move “x” amount of cm’s forward on the saddle to get the same alignment of knee, hips, and heels. Do you still try to replicate the same equilibrium of joints and angles of a rider with cleats more forward, or do you leave his position slightly back?
Set the cleats where they should be on his foot, then fit the rest to that.
IMO, moving the cleats back calls for lowering the saddle vs moving it forward.
Moving the cleats back takes some of the calf out of the stroke (shortening the leg). I wish I could find the study published. It was on gaining endurance. One way was to move the cleats back saving energy used by the calf.