Every part that company sells has that warning, including grip screws. Consider the source, and read up on what you want to do. If you aren't sure of something, ask, or get someone to look at it for you.
The US Army manual on inspecting and servicing the 1911 gives you the basics for testing function and what to look for in the way of possible mis fits.
It is available free via a search online.
I did not know that, and thanks for the excellent tip. I will avail myself of that resource.