Hello HimyKabibble,
about the utility: imagine to use a cnc lathe but you want to move it manually.
If you have 2 joysticks, one for the long axis and one for the traverse slide, with different movement mode, i.e. in the left hand the joystick of the long axis, mode continuous and in the right hand the joystick of the traverse slide,setted up in single steps, 1 cents, you can use Mach3 as a dro, have a zero point etc. and you can turning fast without mistakes because you know at each pressure of the joystick the traverse will move 1 cent.
If you use a common pendant, a part the risk to forget to change the mode, you loose a lot of time.
Are you sure you can not use 3 axis simultaneously?