I'd say the biggest compromise would be in balancing ... when I am riding, and particularly if I need to brake hard, i don't want to have to lean back on the pedals and probably lift up on the bars to lever myself down to compensate for the pressure on the pedals ... or one one pedal, actually.
I know that is where mountain biking started, but I wouldn't want to go back.
As for whether it is possible ... it was in the early '70s, so it ought to work still. I don't see an upside, but it isn't my bike we are talking about ...
