A remarkably simple and cost-effective answer. Essentially it states “get people housing and then it’s way easier to treat the things making them homeless” plop someone in a home and then it’s easier to get medication to them and they stop showing up in the ER 4x a month. Get people housing and then you know where they are to check in on how dependency treatment is going. Psychiatric condition? Way easier to treat if they have a roof, heat, an address to send medication. It is actually cheaper than just doing nothing and allowing people to remain homeless.
But then they stopped funding it in 2015. “Man this remarkable looking approach stopped working!” “Oh? When?” “Right after we stopped funding it!” “Huh, weird.”