[binarycrusader]

  Rent control reverses this, and the landlord loses the
  incentive to upgrade the apartment and otherwise keep the
  tenant happy.

I'll stop you right there; while that may be what happens in theory, it certainly hasn't seemed that way to me in practice.

Perhaps in a market where there is sufficient supply for demand, but in a market where demand is sufficiently high, many property owners don't do more than what is legally required and keep raising their rents.

You would not believe some of the dumps I've been shown by smiling realtors or owners that wanted thousands of dollars per month -- I'm talking about $2500+ a month for a two-bedroom apartment with boarded-over holes in Windows, holes in walls, a terrible smell and carpet that looks like it was last replaced decades ago.

Time after time, the pattern I've seen from experience in the Bay Area has been that owners will do whatever the market will bear -- in a market with severely constrained supply, the market is forced to bear quite a bit.