Lo Pros, Represent

Excuse my ignorance, but I've never seen one 'in the flesh' - what stops it being massively uncomfortable to ride? Is it like riding a road bike in a tucked position where you're holding the bottom of the drops the whole time?

Yes, that is the exact point. So it is as comfortable as riding in the drops all the time which would be a problem for many who ride along wondering what that bit below the hood is for.