My general rule of thumb, and I fully grant that this is as arbitrary a measurement as anything else, is to look at who is pulling aggro, and then look at their gear for threat +/-. When you find someone with threat mitigation that still pulls aggro in a variety of quests...
The real value of things like the spreadsheet and videos is to give you an idea of what kind of damage people are putting out so that you know if you are underpowered (need to reincarnate/farm some gear), about average, or above that (need to watch your threat unless you can tank).
P.S. The rules for the videos are so stacked against monks that it's not even funny, and they still rule the portal. Premium classes are more powerful, otherwise, why buy them?