I hate when coworkers tell we should do thing in a particular way because it’s ”better”. We try the thing and there’s no measurable difference. Well, it was a good idea in their mind, so it must be an improvement. Therefore, they insist it should be kept, even if it makes the code extra convoluted for no reason at all.

And yes. Profiling is great. Often it is a surprise where most time is spent. Today there’s few excuses not to profile since most IDEs have good enough profiler included.