Error in FCP Manual

Can we post errors in the FCP Manual here too?

Version 4, Volume III, Page 297:

"Since OfflineRT media is highly compressed, you can capture a lot of clips to your hard disk. For example, using the OfflineRT format, you can store approximately two hours of video per GB of hard disk space."

This is inconsistent with Volume I, Page 41 which lists OfflineRT between 300 and 500 KB/sec. Page 42 tells us that at the high end of this scale, OfflineRT uses 1.8 GB for 60 minutes. Even at the low end (300 KB/sec) 60 minutes of OfflineRT would take a little over 1 GB.

Anyone care to confirm my math?