I will speak from my personal experience and then I'll let the clerk address it and how it's administered.
In every committee that I've been on, and I've been on dozens of committees at the House of Commons, and on joint standing committees, this is a standard routine motion that we see all the time. It doesn't mean there are certain things that the committee can't discuss at any point in time. It just means that when we're going to depart from our working agenda in any significant way, a motion has to be presented in this fashion in order to do so.
That's my general interpretation of it, but I'll let the clerk expand on that with the more technical details.