[luxtpm]

my point is that currently zoom goes with the forward backwards axe in most games

but you may want to move you head close to the gunsight and zoom out,you cant, this is a busy axe of 6dof

but leaning is a not busy axe because if you want to lean your virtual head you just need to lean your real head, theres no need at all of 6dof for this efect

so if you have 6 axes and one is free to which axe would it make more sense asociate the zoom

edit:

if your view is obstructed by a bar rolling your head will solve nothing