Comments on Profile Post by RezIsStupid

There is no rule against this. The rules state:
Avoid posting multiple threads on the same issue.
Ex. "Server is down" "OMG Server is down" "Why is the server down"
Avoid posting duplicate answers on a resolved issue.
Ex. “Relog on minecraft” “Reboot ur minecraft” “Open and close minecraft”

When making a post agreeing with someone it can contribute to the discussion by numerous means. For example, you can say why you agree or offer another point of view not previously discussed that supports that what you are agreeing with.

Oh ok. That makes sense. Thanks of informing me!

Here is an example of a useful agree post. http://www.mcbrawl.com/threads/28191/#post-392472