^^^^You're on the right track, but try markets where an avg size 1BR starts at over $3500/mo. The general consensus is that New York and Boston are really the only two markets that can provide demand for micro lofts in a material way. And in Boston we're talking a very small area. Even in SF, which is more expensive than Boston for renting, people are still used to at least getting around 600-800 SF for a 1BR in most cases. I currently live in 450 SF and I'm happy, wouldn't consider less (no need to).
Micro will not take off in Jax, ever. There is no reason. Micro is essentially 200-350 SF or less, technically speaking. Who the hell in Jax would consider that when they can get a luxurious 1,200 SF 2BR at many places for around a thousand bucks.