Chained layout dimensions scaled incorrectly?

I, mercifully, haven’t had to touch 2D in a while and I’m having a problem with chained dimensions drawn in paper-space. The file is in mm units, the dimensions are in foot-inch architectural. Now this is JUST trying to use the ‘chained’ function in the Dim command, but if I look at the dimension properties for the dimensions they look correct, but the distances I see on the drawings are scaled by…about 25 times? It’s not quite the mm-> inch scale factor. The first dimension in the chain is right, the rest are wrong–but again the show the correct distance in the Property panel.