Q:

"You'll find that..."

I was in a chat discussing the translation of our project and one of the developers made a joke:

You'll find that the Commonwealth
  spelling [of "member"] is "membre" :)

This is not the first time I've heard the phrase "You'll find that...". What is it supposed to mean and where does it come from?

A:

It just means that if you bother to take a closer look at something, you will see that it is the way described. It suggests that the speaker has experience of the thing mentioned, and is reporting to you from that vantage point.

