Andy,
I agree that you should organize and engage in winnable battles. What I disagree with is your assessment of which battles are most winnable, and at what costs. The facts on the ground are that efforts at legalizing and regularizing status by means of piecemeal legal reforms HAS NOT WORKED, whereas efforts at getting the benefits of legalization by alternative means outside the system has worked to some extent. The existence of large, flourishing shantytowns is proof enough: the parallel systems that they create outside of ordinary legal channels for securing homes, work, property rights, personal security, dispute resolution, community recognition of family arrangements, etc. just are demonstrations of working alternatives to legalization. These alternatives seem to have done a much better job at actually improving ordinary people’s lives on the margins than legal-reform campaigns have thus far.
My problem with legalization schemes and similar legal reform campaigns isn’t that they somehow offend against my sense of purity. It’s that they rarely deliver what they promise, and what they do deliver is typically at very high cost and very low quality. I don’t have a beef with practicality; what I have a beef with is the kind of dogmatic appeal to “practicality” where it is assumed that something must be the more practical option just because it involves compromise with the existing political system and operates according to conventional rules of political etiquette. In fact, I think the reverse is often the case: the political game is typically rigged, and you can get better results faster, cheaper, and more reliably by working out ways to route around the damage.
See also http://radgeek.com/gt/2008/01/26/inwhich/ and http://radgeek.com/gt/2009/02/07/countereconomicoptimism/ for comments on practicality and winnable battles.