As expected: it doesn't work.
Not expected: it doesn't crash.

In fact the whole process goes a lot further than I expected: `rac_deallocDisposable` works, swizzling `dealloc` works, the only problem is that both protocols and blocks don't call `dealloc` when they deallocate, which is good because they subclass `NSObject` and `NSObject`'s `dealloc` implementation can't handle them.

I'm gonna go ahead and say I knew it all along. (Actually I only thought to check classes before you asked)