I've invented my own methodology1. It's called "do the right thing". The way this methodology works is, you "do the right thing".
If the build is too slow, [using XP terminology] you don't write a "technical story" to ask the customer for time to speed the build up; you "do the right thing" - if speeding up the build will improve the team's productivity (which it usually does) then you speed the build up. If the code hasn't been refactored then, do the right thing and refactor the code so the team can remain productive - the story isn't finished if the code needs refactoring. If something can be automated, e.g. the deployment process, then do the right thing and automate it. If some functionality doesn't have an automated test, then write an automated test for it. You don't need to ask permission to do the right thing - it's your duty and your right.
I have seen teams that have not done the right thing; a lack of refactoring, a lack of automatation, and a lack of automated tests are major causes of low productivity, low quality and low morale. You don't need to be "given time" to do the right thing - doing the right thing makes your team more productive and saves you time. Do not give in to short term time pressures - successful software2 lasts longer than anyone expects and takes longer to develop than is typically planned for. I have never seen a software project benefit from taking short term decisions. I've never seen a software project be unproductive because too much has been automated or through too much refactoring. I have seen many projects where there has been a direct correlation between not doing the right thing and the areas that have caused "unexpected" problems, taken longer than they should or resulted in production bugs.
1OK - not really invented, not really mine and not really a methodology. Joe Newton, Joe Walnes, W Edwards Deming and Kent Beck have all influenced this article/rant.
2Also known as legacy software.
I was described yesterday as the Charlton Heston of pair programming. Was this because I'm handsome and charismatic? No. it's because if you want the keyboard, you'll have to pry it from my cold dead hands.