I don’t know much about those specific registers, but in general you can modify “settings” registers like that freely. Well, on the Wii U you can’t (you need to be operating in the kernel to have permissions for supervisor level instructions) but I believe the Wii has no such checks.
For example, if you modify the DR bit of the MSR to 0, as long as you don’t set it back, every load/store operation you do afterward will be with reference to the physical (not effective) address. I think setting HID0 would work similarly.
For example, if you modify the DR bit of the MSR to 0, as long as you don’t set it back, every load/store operation you do afterward will be with reference to the physical (not effective) address. I think setting HID0 would work similarly.