Are encoders supposed to appear as two buttons or as an axis? For me they show as two buttons. That surprised me some, but thinking about it I could guess why it might be necessary, although then I wonder why the special configuration...
with 3 buttons you can build "virtual axis" (1 button - axis step up, 2 buttton - axis to center, 3 button - axis step down). encoder with push just give to you 3 buttons.
