:GetRoleInGroup() will stay up-to-date [Wiki Question]?

I hope someone can help me out with this. This is more of a wiki question, I know how to Script so that's not the problem.

So basically, if you go to these two pages: http://wiki.roblox.com/index.php?title=API:Class/Player/IsInGroup

http://wiki.roblox.com/index.php?title=API:Class/Player/GetRankInGroup

You'll see a thing like Notes Please read that before you continue.

Now my question is, does that note also count for the YieldFunction :GetRoleInGroup() ? Since, you don't see that Note on the page, here have a look. http://wiki.roblox.com/index.php?title=API:Class/Player/GetRoleInGroup

So that means :GetRoleInGroup() will stay up-to-date, server-sided & client-sided? If that's the case, then why don't :GetRankInGroup() or :IsInGroup() stay up-to-date?

Thank you for reading.