I had a feeling if I posted that, I'd be at risk of unchecking the box. My defense to keep the box checked: My understanding is that the interference of classical waves produces a different pattern than that of quantum waves. Granted, I don't have such a great eye that I observed the pattern on my garage wall, and probably already a couple IPA's into it anyway, said, "Yep, that's it! Let's check the box." I assumed, given it was a laser, that the interference pattern I saw must be quantum interference. If the classical kind of interference can also happen with a laser shooting through two nails, then it's checkmate and I have to uncheck. I assumed that enough experiments have been done with lasers that it is established as always a different pattern than water's (or bullets) when going through two slits. 100% of the time. Don't soften the blow, this isn't Sic et Non, and around here, we're happy to learn that we're wrong about something. If it's possible I saw something other than quantum interference, let me know. (I'm reading your account of Young as confirming that a laser in my scenario would produce the same pattern as if light were a classical wave, and so the box has to be unchecked)
Wave interference is only weird if a single particle does it
to be sure, because I either missed this, forgot about it, or the youtube videos I watched in the past were wrong: Normal light, or my laser through the nails interferes like a stream of water in the same scenario. The shift in pattern only happens at one quanta at a time?