My memory is not perfect on this matter, but I'd swear that we only had to use one patch cable at CHQM in 1971-72 for stereo inputs. I never noticed the difference at the time (from the mono ones I was used to using at UBC Radio), but was there a stereo version of these patch cables?
FYI, I only recall having to use patch cables when we were remotely running the tape drives in the FM control room, from the AM control room. They were patched in to replace the turntables. It was an eerie feeling pushing the button and hoping that the tape in the other room (there was an announce booth between the AM and FM control rooms) would actually start rolling.
You also started doubting yourself that you had put the tape hubs on tight enough, and kept imagining that the tape would fall off the drive with you so far away and unable to quickly solve (or prevent) the problem. I guess it didn't help that the operator who trained me warned me about that happening.
Actually, there was one even more eerie experience. Running the AM station off the automation machine. Because you couldn't even see it from the AM control room. You just pushed a button and only knew if something was happening when you heard, or didn't hear, any sound coming out of the monitors. Only did that once and, silly me, it was actually my idea. And a bad idea at that.