[Python-ideas] Deprecating rarely used str methods

[random832 at fastmail.us]

On Fri, Aug 9, 2013, at 23:58, Chris Angelico wrote:
> Oh, I can see the other side's arguments. If str.format existed and
> str% didn't, there would be insufficient grounds to add it. But they
> both exist, and the arguments for removing a feature have to be
> insanely strong. Status quo wins easily.

What exactly was the sufficient grounds for adding str.format, and for
giving it its own minilanguage instead of using the one % already uses
[with extensions like being able to use both positional arguments and
%(keyword)s, and maybe something like %1$s for explicit positional
arguments]?