After reading your take on the possibility of your Dad going to a Japanese car, my bet is that the Cadillac Division of GM lost quite a few old faithful to other (non-GM) makes because of the constant problems with the '96 - '04 FWD Northstar drivetrain.
Hard to get figures, but if you figure that maybe 2% of FWD Northstar owners come and go in the relevant Forums here, then the real world numbers of problems is proportionally more......and some of them might jump ship. Your wallet can only take so much.......
I'm 35 miles east of DC, there are a lot of commuters, and I now see a fair number of newer Devilles in various model packages. Maybe there's some hope left

. CTS's here are either red or black and driven by crazy blonde women with a latte' in one hand and a cell phone in the other, OR, the ultimate: latte', talking on the OnStar
and applying eyeliner at 75.