To give a more concrete example: I have recently seen a very complicated piece of logic checking whether a subsequent code should be even invoked, but it was hidden in a debris of core logic and other verification. It easily could have been separated and rewritten as a series of early returns and this is what a precondition is. I’m sure someone who wrote the code had it in their mind but was not familiar enough with the early return technique to embed this in code. Had they been, their brain power could’ve been utilized more efficiently.

The answer is yes, both words are related to idios, "own", "self", "private".