This is probably BrewDog's big 'fuck you' to Schorschbräu, a German brewer they were more or less having a pissing contest with ever since BrewDog took the strongest beer title away from them with Tactical Nuclear Penguin. Schorschbräu fired back with Schorschbock 40% and actually had the balls to offer BrewDog their ABV-amping secrets for a price. BrewDog responded with an upturned middle finger and 'Sink The Bismarck!' at 41%. Then Schorschbräu released Schorschbock 43%, once again taking the strongest Beer title. I can only imagine what blind drunken rage drove BrewDog to release this trump card. Unfortunately, it's kinda for naught if the beer sucks.
I actually have a bottle of TNP sitting in my collection for a special occasion, and I've had Sam Adams strongest beer, Utopias (26%). Utopias was mind-blowingly fantastic, but I've been hearing a lot of mixed reviews about all the stronger beers above it now. Utopias was so good because its boozy character was so offset by its flavor and character that it's a joy to sip. And this whole 'strongest beer' war would really be all for nothing if the resulting beers don't taste good.