A number of players with the older pairing rules erroneously thought it was higher-rated gets due color even when a lower-rated player had more points and was higher-ranked. Now with full color history you can get a situation like what happened at one US Open where a player in round 9 couldn’t understand why he got black against his opponent (same score, he was higher rated, they had both gone BW in rounds 1-2 and WBWB in rounds 5-8, but he had a black in round 3 and a bye in round 4 while his opponent had a bye in round 3 and black in round 4, so it alternated from his opponent’s round 4 black versus his colorless bye - BWbyeBWBWB gets white before BWBbyeWBWB).
At this point I’d guess that almost all NTDs can explain more complicated pairings (many did them by hand before computer programs were available and had to understand them before making them), most ANTDs can explain them, a lot of SeniorTDs, some LocalTDs and the occasional ClubTD. Also, TDs that don’t have a solid grasp of pairings won’t always recognize when they have settings on their pairing software that causes inferior pairings (the proper software settings can let the computer pair like an NTD while an oversight can cause the computer to pair like a LocalTD).