The companies responsible for this comment is applying it
all wrong. They are applying a computer style onto something that requires a typographical style. They have the mindset that warnings are to be placed onto the
same page, just like in a basic web page or
online documentation.
WRONG!
What they should be doing in fact is to warn either beforehand that "the following X-number of pages are intentionally left blank" or afterwards "the preceding X-number of pages was intentionally left blank". These statements are more accurate.