It's been busy over the last five years, and I got lots of froth when I opened it, fading after a moment or two to leave a more appropriate creamy topping. The aroma is a mix of boozy oaky spirit and sour and meaty old-beer smells. It's slightly off-putting. The flavour is better, thankfully. It's clean and tart, lacking the weighty warmth of fresh Clotworthy but replacing it with an interesting blend of farmyard funk and sweetly honeyish Irish whiskey. Where beers like this tend to stick to the palate, this one clears off quickly, more like a Berliner weisse or cider than a barrel-aged porter. A building acetic quality gets a little bit much as the half litre goes along, though fails to spoil the party.
It really is interesting how much this one has changed since it was untransformed 2009 Clotworthy Dobbin. The base beer's dark malts are still there, in ghost form, now thoroughly fused with the whiskey, and then the years in the bottle with whatever complex microfloral battle was taking place have attenuated the whole thing and added the complexity of a Flanders red. One has to imagine that modern sour beer styles have experiments, or rather accidents, like this somewhere at their roots.