I finally had the time to look more closely to the issue, and I'd like to hear some comments on the info visualization.

Currently we have --help option to print:

 <usage + additional details about execution + more rigorous testing>
 <options>
 <verbosity>
 <selecting tests>
 <special runs>
 <additional options details>

Now, AFAIK argparse it's not so flexible, so we have to draw a line and choose a trade-off.

F.e., the additional options details: they can't be added in a help='..' kargs but they should be nonetheless be displayed when passing --help to regrtest.py.

* <options>, <verbosity>, <selecting tests>, <special runs> can all be grouped up into argument groups.

* <usage> can be managed "twisting a bit" the usage='...' karg of argparse.ArgumentParser

* but what about <additional options details> ? should we add that to the usage='...' text? or should we somehow override the print_help() and show

 <usage>
 <options & options groups> (this is standard until here)
 <additional options details> (appending the text after options)?

or something different I still don't imagine? :)

Cheers,
Sandro