Because if the numbers don't work on overhauling a single block based on the tax revenue generated by that block, they also don't scale up to work if you draw t

Because if the numbers don't work on overhauling a single block based on the tax revenue generated by that block, they also don't scale up to work if you draw the tax revenue in from "elsewhere." Everywhere else ALSO has its own road, sewer, etc. to maintain, not to mention fire and EMS services.