So how the hell would he even trade a 1Ds1 for a 5Dc?
Regardless of how nice a 5D is, the 1Ds is still pretty sweet - Full weather sealing, Metal construction, and an AF system that actually works well. Sure, the 5D takes absolutely awesome photos, but having used both cameras fairly extensively, they both take pictures, and both take them well. If I had to choose between the two, I'd take the 5D on weight alone, much less the newer processor, and everything.. but since this guy already has a 1Ds, I don't see the point in switching.
Have a nice day, Bluename.