Message 237049 - Python tracker
Don't break backward compatibility. It's not like this was reported as a bug that caused a problem for real world code, it is about theoretical consistency. The risk of breaking someone code is much higher than the benefit of any such consistency, when talking about a bug fix.
Aside from that, however, I see request.('GET', '/') and request.('GET', '/', '') as clearly *different* from an API call standpoint, so I would in any case preserve the existing behavior.