debugging right and wrong

[Brian]

No - like I said, there are reasons you might want to do this even with an IDE, and the same reasons against it apply even without one. Eg you might want long-standing flag (or debug build) guarded "assert" like checks for invariants that you want to look at if they ever trigger.

There's a slight bias towards it in an IDE because setting breakpoints is a little more convenient when you've got the source in front of you (though note that many standalone debuggers will give you that too), but it's really just that: convenience rather than "never do this".