I have done it for the experience. The benefit you gain, after following the above procedure, is that the first runnings wort is full of enzymes that get right to work on the new grain. The end result for me was that I ended up with a sticky wort at 1.120. The end beer fermented very nicely and has been aging. The one bottle we cracked is delightfully smooth.
That said, I do not really need 10G of barley wine, or even 5, so I generally go with a first and second running strategy where I get a huge first beer and an awfully respectful second beer. Third beers are too astringent for my taste, especially since I am not blending. Example: Imp Stout pushing around 1.130 (top range of my measuring equipment) which yielded a second beer, a porter, at 1.076 which finished at 1.018. I did cap the mash for the second beer with an additional 2# of caramel malts.
The challenge for me is that I need two boil vessels, but that is a small headache given the benefit of two beers for not too much more investment.