Yeah, though one shouldn't underestimate Jacky Fisher's role in the concept of the battlecruiser either. He had a big bright idea and he wasn't gonna let it go - it was the ship he really wanted to build (Dreadnought was his compromise that, ironically, proved to be the right idea in the end - but not what he really wanted to built). The battlecruiser was his ship and he was gonna see it through, and his increasingly outrageous designs in later WWI only show that.
Not that cruiser killers didn't have their niche, of course. The idea kind of survived into WWII, but never saw much use in reality.
Then you could also argue that battleships as such were, in the end, also a failure. The predictions of Mahanian doctrine that they were built around never came true - the great decisive line battle never happened, while billions and billions were sunk into building the things by many nations, when the real masters of the sea turned out to be the humble airplane and submarine.
And yet of course you can't not love the designs (assuming you like fast, powerful, intimidating, deadly-looking things)
