It has to do with conceptually differentiating between an actual gate that has 2 independent signals to make a comparison, and the ability to compare 2 things with 1 signal. I thought it was possible in a system for comparison to be carried out by 1 signal determining the state of 2 switches, and somehow creating logic from this without the need for 2 independent signals. For example, in a situation where 2 bits are traveling down a wire in series, in order to do a comparison on those 2 bits, each must be mux'd (if that's the term) onto their own individual wires, and then fed through a gate(?) There's no way to compare them outside of a gate(?) I thought perhaps there was some "comparison capacity" aside from each bit having to be "converted" into its own independent signal on its own wire and then sent as 2 inputs into a gate.I don't get the part about "flicking 2 switches with one signal". You have mentioned this several times, and I still don't get it. An AND gate requires at least two inputs. Of course, you can use the same signal to control both inputs, in which case your AND gate degenerates to a follower, or buffer (non-inverting).
RB
P.S. Thank you all for your very helpful replies...