Yes, but the attitude just rubs me the wrong way. If they suggested the voltage divider, it would have been a good opportunity to instill careful engineering an

Yes, but the attitude just rubs me the wrong way. If they suggested the voltage divider, it would have been a good opportunity to instill careful engineering and testing practices. They could have said something like "this will fry your GPIO if you accidentally send 18v, so make sure to test the circuit with a multimeter or scope!" Instead, they suggest throwing an expensive part at the problem, supporting the attitude that you can't trust your own engineering. At least they mention that there are other ways to do it. I dunno, maybe it's two different, equally valid attitudes. I guess I dislike it for the same reason I prefer C++ over Java.