But you might not even need to understand the edge case, you just need to know that it's there, and it means the code is more complex than it really should be.

But you might not even need to understand the edge case, you just need to know that it's there, and it means the code is more complex than it really should be. The code itself cannot reasonably communicate the developer's true intent, and so a short comment can remove any ambiguity even if it doesn't explain the issue in full. The GP assumed incompetence, when it was really pragmatism.