If you keep increasing the image offset indefinitely, it can end up with huge offsets like 100,000 pixels offset. Then you run in to precision issues since not all GPUs can do things like render textures accurately at such large offsets.
The workaround is simple: wrap around the offset back to 0 once it goes larger than the image size.
I just added a note to the manual entry to cover that since I've seen people running in to this before.