I've spent the last couple of days back with The Refactoring Project. They've done well in my absence. They managed 3 releases; all correctly tagged and repeatable. They started some refactoring of their own and, at first glance, it looks like they've taken on board lots of the suggestions I've been making over the last months. They've fixed a couple of new bugs in the FX code and whilst doing so found that a) the bugs were easy to locate, b) they were easy to fix with very localised changes, and c) the new code was much easier to work with! They even ran the tests after making the changes! All in all quite a reassurring result.
Now, of course, I have to move away from the relative safety of the newly refactored FX code (complete with tests) and back into the pile of code that has yet to be touched... Still, at least things are heading in the right direction.