It may depend on the CS6 version there are 3 Perpetual Mac is version 13.0.6 Perpetual Windows version 13.0.1.3 and the Subscription version 13.1.2. I use the Subscription version 13.1.2 and it return the correct values for the shape layer. I doe no have CS5 installed but do have CS2 installed it return the incorrect values you posted. So I tried my purposed work around in CS2 it would work. The size was also wrong for then bottom right corner position was off like the top left.
