Also when applying the mantra "Dont repeat yourself" (DRY) it can have the opposit effect; that when you are optimizing a hot loop, like a game render loop you inline everything and discover there are repetitions that can be vectorized or removed/optimized. Maybe because you applied DRY and abstracted too early or what not.
Yeah... DRY is probably the most over-used principle (likely bc it's so easy to identify). I like "AHA" (Avoid Hasty Abstractions) as a counter-balance.
