I scooped up a 1971 Mouton Rothschild from an original owner at a solid price, and was hoping for decanting advice from the board, as I have very little experience with older Bordeaux.
I’ve had it standing up for a couple days, and was planning on popping the cork and slow-oxing for an hour or so before drinking…but I’m wondering if it will even need it.
That would be my instinct, too. It was not a powerful vintage – second growth 1971s I had in the 80s seemed pretty mature – so the wine may have crested, even though you say it’s been well stored. But try a bit when you first pull the cork. If it’s dark and brooding after a little while in the glass (unlikely, I think), then consider a decant.
I would also go the slow-o route, as '71 was not a big tannic vintage (as already mentioned). But I would enlarge the surface area to silver dollar size (if it’s not already there) by taking a small exporatory taste, and then give it 3 -4 hours of slow-o, and be sure to serve on the cool side, as this will strengthen the fruit. A few hours of slow-o should actually strenthen the wine and make it healthier!