I think we're discussing the same thing from two different angle, but let's just say if developers take a bit of time upskilling and finding new ways to solve problems more efficient you'll have a performing app and save time finding where to optimise in a large code base.
Back to your point, a developer spending a bit of time reading will help much more than simply code and wait for a bug or a ticket to be raised later on performance.
Last you're just taking one of the points and generalising it, perf tuning is a broad aread, this is one of the thousands
and in those cases i would rather a past developer had put their time and energy into making sure their intent is clear before getting clever.
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