>> 4) she got annoyed that two completely different notations where used 
>> for two very close concepts
>
> This is a good point, and we are trying to move to the arg=default
> notation.  Unfortunately there are still places that use the old
> notation.  C functions that have optional arguments but don't accept
> keyword arguments are a bit unusual, and IIUC in most of the cases
> that's an implementation detail that could be removed.

So would it be worth the effort to identify each such place in the built-ins/stdlib and eventually change them all?  I've seen support for doing so in other tracker issues and think it's a good idea personally.