Twisting wires work for cross-talk between them, if both would be signals at a higher rate it might work, like in ethernet cables. Tho in ethernet its not only for that, also for debugging, so a tester can see a wire is broken, and by measuring the interference it receives back from its pair and kowing the coupling then the tester can deduct exactly at how many meters forward that wire is interrupted. So in an application where that wire is not easily accessible, user would know exactly where to start digging.
But in case of our endstops we dont have a frequency to speak of. And we have only one signal and the other is simply ground, so why bother twisting them. I suppose normally it is not the case of signal affects the gnd because "gnd is gnd" and would just sink that. And ofc its not the other way around either, so even if gnd might raise a tiny bit, it would be far from enough to affect the signal, and again no frequency to speak of.
So i suppose the issues come from interference with cables from motor, or heaters with pid, these would be basic radio emitters, so imo is different case. If you do twist in this scenario, you basically increase the length of wires and probably increase your "antenna" length and increase the "receiving capability". At least that is what i would expect.
Imho to reduce or eliminate interference from steppers and heaters, can not avoid shielded cables. So again imho, ned to use shielded cables and have the shield at ground, at the "motherboard" end only (not at both ends!). So shield should not create a gnd loop. Also shield should not be used for signal coz that would defeat the purpose. So at motherboard end you have 3 connections, shield, gnd and signal, and at the other end only gnd and signal for endstop. What shield does it makes a "faraday cage" around its internal wires, and takes all interference, and internal wires can not receive interference from outside. This is solution in my opinion.
One "attempt" to minimize you "antenna" length and hence its "exposure" would be to use only one logic pin for all endstops and have the endstops wired in series. Because i think this simply minimizes the wire total length, just for that. But need an firmware to be aware of this, and basically each time it homes to know to back away like 1mm untill that endstop is not triggered, and only then to check for other endstops, one at a turn. This is how most traditional cnc use this, probably because back in the day when were used interfaces like lpt port and logic pins came at a premium. Currently i think most reprap firmware dont know to use them like this, which is a pitty. At least i think marlin does not work like this, it just homes and remains in a position where that endstop remains "triggered" i dont know if it an be set to "back away" from that. Other attempt to minimize would be just make the endstop cabling to be as far away from motors and heaters. Again all the above etc, just my opinion.
But in case of our endstops we dont have a frequency to speak of. And we have only one signal and the other is simply ground, so why bother twisting them. I suppose normally it is not the case of signal affects the gnd because "gnd is gnd" and would just sink that. And ofc its not the other way around either, so even if gnd might raise a tiny bit, it would be far from enough to affect the signal, and again no frequency to speak of.
So i suppose the issues come from interference with cables from motor, or heaters with pid, these would be basic radio emitters, so imo is different case. If you do twist in this scenario, you basically increase the length of wires and probably increase your "antenna" length and increase the "receiving capability". At least that is what i would expect.
Imho to reduce or eliminate interference from steppers and heaters, can not avoid shielded cables. So again imho, ned to use shielded cables and have the shield at ground, at the "motherboard" end only (not at both ends!). So shield should not create a gnd loop. Also shield should not be used for signal coz that would defeat the purpose. So at motherboard end you have 3 connections, shield, gnd and signal, and at the other end only gnd and signal for endstop. What shield does it makes a "faraday cage" around its internal wires, and takes all interference, and internal wires can not receive interference from outside. This is solution in my opinion.
One "attempt" to minimize you "antenna" length and hence its "exposure" would be to use only one logic pin for all endstops and have the endstops wired in series. Because i think this simply minimizes the wire total length, just for that. But need an firmware to be aware of this, and basically each time it homes to know to back away like 1mm untill that endstop is not triggered, and only then to check for other endstops, one at a turn. This is how most traditional cnc use this, probably because back in the day when were used interfaces like lpt port and logic pins came at a premium. Currently i think most reprap firmware dont know to use them like this, which is a pitty. At least i think marlin does not work like this, it just homes and remains in a position where that endstop remains "triggered" i dont know if it an be set to "back away" from that. Other attempt to minimize would be just make the endstop cabling to be as far away from motors and heaters. Again all the above etc, just my opinion.