In my time in the Mil, initially we had "Flares Ground Indicating" (FGIs) that were laid out in a pattern in front of the Tower before night flying, in case a Landing Gear check was required during the evenings' excitement. These were lit by an AATC (ATSA) with a 'portfire' on the ATCO's instuction at the moment critique as the 'distressed' aircraft initiated his fly through; timing was all important as the FGIs burned for about 3 mins and they all had to be lit (which took about 3 minutes!) to get enough light to illuminate the underside of the aircraft as it flashed through. Saw it done once and it worked, surprisingly enough.
FGIs were replaced by UCLS later, which was far more convenient. However, it was drummed into me at Strawberry that the only thing that could be reported over the RT was "Your landing gear (meaning the whole thing) APPEARS down and locked" or "Your port undercarriage (meaning the specific element) APPEARS unlocked (or the like). This would seem to be an early example of individuals' @rse covering before the days of serious litigation.