If I have to joint any man made stuff I use the planer with the fence as far back as it will go so that it doesn't ruin the knives anywhere bar the far end. I can then bring the fence forward slightly when I need to work timber.
Your tip will work perfectly as described of course but I guess it depends on your work patterns whether it's suitable for any particular person. A pro cabinet maker friend of mine who (admittedly) has a 20 inch planer, likes to keep the first couple of inches nearest the fence pristine for jointing door edges and the like. So whenever I beg the use of his machine, I am reduced to 18 inches Actually, I think it's the ten feet of infeed/outfeed table that I am most envious of!