I laughed at this bit, because I've also tried to debug things only to find it wasn't telling me what was wrong with my code (my own error, perhaps - a forgotte

I laughed at this bit, because I've also tried to debug things only to find it wasn't telling me what was wrong with my code (my own error, perhaps - a forgotten --verbose or -v): > Turns out macOS's IOHIDManager silently blocks the longer HID++ report format you need to actually write to it. The OS just drops the packets. No error, no explanation, nothing. I found this out after writing a pile of probe code and staring at empty responses for longer than I'd like to admit.