That's right, thank you! I just looked it up, I can't believe I didn't check there first. I had this funny feeling it was one of those odd things that doesn't seem to follow the rules stated in the manual.
Thanks for clearing this up, it makes perfect sense now.
If anyone reads this and happens to know the statistical odds on a DRN for how much of a gem difference is needed to give ~98% safety, I'd be curious of that, just for reference. Thanks again.