>> Can any city provide a net increase in 5,000 housing units? Well, that’s a speculative question, but one thing we can do is ask if any city did produce 5,000 extra housing units beyond household formation over the last 5 years

Calgary (Alberta, Canada, not Texas) added triple that in 2014[1]. Since the province's economy is commodity driven the major city centers are accustomed to boom and bust cycles and are used to adding housing quickly. Also of note, Calgary has rated quite high based on a number of other metrics given by Amazon[2] (though, to be fair its really hard to trust all bias is left behind in these analyses)

[1] http://calgaryherald.com/life/homes/new-homes/calgarys-housi... [2] http://www.cbc.ca/news/canada/calgary/amazon-headquarters-ca...