>>> you absolutely don't care whatsoever about performance and can guarantee that you never will.
Those are actually pretty good bets, better than most other technological and business assumptions made during projects. After all, a high percentage of projects, perhaps 95%, are either short term or fail outright.
And in my own case, anything I write that is in the 5% is certain to be rewritten from scratch by the coding team, in their preferred language.
Sure but you're still screwing yourself over on that 5% and for no real reason - there are plenty of languages that are just as good as Python (or better!) but aren't as hilariously slow.
And in my experience rewrites are astonishingly rare. That's why Dropbox uses Python and Facebook uses PHP.