Feb. 24, 2012
4:39 p.m.
It is a burden for some people to learn and remember the exact details of both systems and exactly how they differ. Having both in the stdlib hurts readability for such people. I would prefer that the stdlib only used {} formatting or if not that, that it only used the simple, hard-to-forget forms of % formatting (%s, %d, %f, without elaboration).
If that issue was getting serious, I would prefer if the .format method was deprecated, and only % formatting was kept. I doubt this is as much of an issue as you think, though. Regards, Martin