quasit1
If it's too slow, then you probably have an issue with which algorithm/data structure you chose and would have had the same issue in another language.
The biggest issue I have with C today is that you can't trust that your compiler actually generates code that is 1:1 with what you wrote. I'm not talking about UB here, your compiler can actually remove code/checks even though you don't invoke UB.
Then we have UB, I think UB should be removed from the spec completely. There probably was a point in time when leaving stuff as UB was the best option, but today speed is seldom the problem, correctness is.
I no longer work as a C programmer, but I still love the language and I really enjoy writing C code, but I really would like to get rid of UB and have a compiler I can trust to generate code even when I turn on optimizations, and having optimizations off is not an option either, since it can generate broken code as well, so...
So much important work is not really possible to demo in a way that most people understand or see the gain it gives either.
I think, from previous experience, that demo-driven development sort of works if you are a company or project in the start up phase, because there are a lot of stuff to demo and the development goup(s) can get quite a boost from the excitement it generates.
So after a few iterations you just say "fuck it" and implement it as specified and then hope that you get a chance to fix it before shipping it (or that it doesn't become your headache later on...).
I sometimes read code for fun. Some code read like an essay, some like a book and other code read like a collection of poetry. So I feel as if all 3 can apply, sometimes some of them at the same time.