This idea started earlier in the week when I pitched the idea of a "tumbler lock" mechanism to panic: a mechanism that allowed checking against all three of the needle elements in parallel. The first implementation of it was pretty much a physical copy of a tumbler lock, which meant it was bulky and slow. Eventually I settled on this version of it, which encodes the needle into a large stick, then allows each of the 4 possible needle positions to either pass or fail depending on whether it matches. If it matches all 3 in order, it passes the gauntlet and is used for simple presence conditionals.