No guest has ever noticed or asked about the second set of drivers going in and out of sync other than the occasional rivet counter who knew it in advance and was looking to stir the pot.
No guest has likely dished out 1600-1700 bucks for one of your locomotives.
Or saved up for one. Or intended it to be the last major piece in his/her collection.
Well, I wouldn't call them "guests" but, as part of the former Independent Hi-Railers, MidWest Division, we generally received lots of comments/questions about the sounds of the various articulated steam locomotive models, many of us ran. So, yes,,,,,,,,they DID ask about the two separate driver sets under one boiler, and "funny" sounds as it ran.