Over at Greater Greater Washington, David Alpert is sharply critical of what he believes is the Gray administration’s decision to delay the development of a new neighborhood in the hopes of luring a Washington Redskins practice facility.

Alpert is a smart guy when it comes to urbanism: All things being equal, it’s vastly better for a city to create a new community—full of neighbors, stores, street life, etc.—than to build even a stadium, much less a practice facility that will (or should) ordinarily be closed to the general public And while there are a number of reasons, such as the close proximity of homeless facilities and D.C. Jail, to explain why the 50-acre RFK Stadium-area parcel known as “Reservation 13” may prove tough to develop, a mayor’s desire to buddy up to a sports franchise really shouldn’t be one of them.

What baffles me more than the apparent urbanist failure here, though, is the politics. The District over the past few years has found itself tied in knots over gentrification. And while the mayor has not embrace the issue like some of his allies, his administration came to power thanks in significant part to widespread public anxieties about the rising cost of real estate, and the changing demographics of residents, in a host of D.C. neighborhoods. People who share those fears ought to be embracing this vision of a new neighborhood along the west bank of the Anacostia.

How’s that? After all, it’s a good bet that any new neighborhood in Reservation 13 would be full of the affluent myopic little twits viewed with suspicion by much of Vince Gray‘s base. But at the same time, it’s not like the absence of a new neighborhood would keep those folks out of D.C. Rather, they’d simply do what they’re currently doing: Moving into  existing neighborhoods, with all that entails.

People worried about richer new residents pricing longtime Washingtonians out of their houses, it seems to me, can get at the problem two ways: On the supply side or on the demand side. And most would agree that just about anything that reduces demand for D.C. real estate is a bad thing: Demand falls when crime rises, schools get worse, services tank, and so on, all things that hurt blue-collar residents a lot more than they hurt yuppies. That leaves supply. It’s complicated, but more inventory in one place—say, because we’ve embraced mixed-use developments in heretofore suburban-style parts of the city, or done something about height limits, or enabled new neighborhoods in areas like Reservation 13—might  reduce the pressure on longtime residents elsewhere.

There are a bunch of reasons why Reservation 13 isn’t a perfect test case. But ultimately, it’s hard to take anyone seriously who says they worry about gentrification but doesn’t fight to develop more new housing.