"It is de rigeur if you¡¯re remapping IP table entries (in my experience at least)¡I¡¯ve never thought t bothersome enough to worry about though"
Me neither, it's a useful notification in that circumstance, but I'm not changing any IP table entries.
"...nor can I remember it occurring when I¡¯m not remapping entries"
So, you haven't experienced this is what you're saying.