I don't consider it an argument; it seems more like an opinion, much along the lines of "Should you bring more than one bass to a gig in case of emergency?"
And I don't get the "I've never seen it, so it must not happen" line so common here on TB. There are pictures of split and cracked fingerboards all over the internet. Saying you haven't seen or experienced it is pointless.
The official websites of prominent guitar builders such as Taylor, Gibson and many others do not discourage the use of oils for unfinished boards; in fact, they subtly encourage it within reason, and for more than cosmetic reasons. And, again, it can't hurt, unless it messes up that perfect hue of your board that you're so fond of.
As with all 'net info, I encourage the reader of this thread to do some research and use your best judgment. Just like bringing more than one bass to a gig, I'll go with an ounce of prevention (and the accompanying peace of mind) just about every time...