Quote Originally Posted by jamadagni View Post
Why never?
Because of two reasons.
1. All changes will be overwritten next time you save the file from within Designer,
2. You have to create a real widget class anyway, so there is no point in modifying any of the generated files as you can do the same elsewhere without pushing yourself into trouble.

Ok, three reasons...
3. It's very prone to errors.

I realize that it can be labeled not recommended
If you're willing to say that aiming a gun at your head and pressing the trigger is not recommended as well, then I can agree with what you said.

but I have found it a quick way to make tiny tweaks and some cleanups that Designer won't do for me.
What kind of tweaks? I don't know if you're referring to modifying xml files saved by Designer or files generated by uic. I guess the former and I really can't see any possible reason to do that...