I think that it's useful to distinguish between code that one has an intimate knowledge of / intuitive sense of and code where one does not fully understand. F

I think that it's useful to distinguish between code that one has an intimate knowledge of / intuitive sense of and code where one does not fully understand. For example, I find printf-like debugging and using stack traces from Valgrind to be very useful for debugging my own code; however, at work, when I have no idea where the problem is, something like gdb or the debugger of Visual Studio really comes in handy.