As we learned with our LC oscillator "diversion", sometimes it's ok to try something out and it simply doesn't work. Along the way, you can try ideas out, test your understanding and - sometimes - a negative outcome is just as valid as a successful one. And if something doesn't work as expected, it's fine to just say "ok, let's try something else".
But sometimes, things go wrong because you've been an idiot. The only thing we learned from this latest effort is that ordering components without fully understanding their format/package is a bad idea - here are some SOT559 hall effect sensors:
Even for SMT fans like us, there are limits to how small you can go!