Mark,
It seems to me that even with a switch that it would be glitchy.
With a 2 bit encoder, only a 25% chance that they would be parked in the same state.
So 75% of the time, the state will be changed just by flipping the switch and not even touching the encoder.
Since encoders are Grey Encoded, I would also expect some additional 'software glitches' when the state change is nonconsecutive.
e.g. a jump from 00 to 11? (when from a 00, you would expect the next to be 01 or 10? to calculate the direction)
You might be happy with it for your needs, just some things you might notice.
A couple of turns and you should be good to go, just not back and forth between the 2 encoders for fine adjustments.
Rgds,
Gary
