Nice zero flex levers there
The shims allow you to run both v or canti bit like the screw on the avids ,think you remove the bottom one
And use the middle one to hold the nipple I seem to remember you fit one from the other lever upside down to take up the play
No, they are v-brake design through and through.
Both in are for beginners, middle is for if you like that feel, both out is the proper v brake setting.
The cable pulls quickly while there is no force on the pads, then when they hit the rim they switched to the inside setting and you get increased force and greater modulation control.
This setup is still used to this day on their v-brakes. At least till m770 anyway, not looked after that.
Practically the same way as 'servo-wave' works on the canti levers but without the forced channels. It all written down on the instructions.
I'm not saying if you fix it in the inner setting it wouldn't be good on canto as I don't know. But that is not the design.