My rule of thumb has been "comment stuff that isn't the naive solution", basically anything that would make someone think "wtf is this" the first time they read

My rule of thumb has been "comment stuff that isn't the naive solution", basically anything that would make someone think "wtf is this" the first time they read it. My biggest headache right now has been getting high-throughput with SQL and as such I've had to do a lot of non-obvious things with batching and non-blocking IO in Java to get the performance I really need, and as such a of the "obvious" solutions don't work (at least with a reasonable amount of memory). Consequently I've been pretty liberally commenting large segments of my code so that someone doesn't come in and start bitching about how "bad" my code is [1], "fix" it, and then make everything worse by rewriting it in a more naive way that ends up not fulfilling the requirements. [1] I have since stopped doing this, but I'm certainly guilty of doing this in the past.