"Depends what you call a BC, and what you call a battle line."
That's an important point. A lot of this hangs on points of nomenclature, and a lot of misconceptions have evolved from their into ossified hindsight.
It bears repeating that battlecruisers were simply outgrowth of the armored cruiser, whose role included engaging enemy battleships from postions of tactical superiority. I'm guessing this is what is meant by "speed is armor," and in this very limited sense, it is a valid statement.
Not one BC sunk at Jutland owes its loss to a BB; the fatal blows were all struck by other BC.
If we adhere strictly to official nomenclature, only one battlecruiser was ever sunk by a battleship, and that was Hood sunk by Bismarck. Also, only one battleship was sunk by a battlecruiser, and that was Bretagne sunk by Hood. Deviating from official nomenclature, we can also say the BC Kirishima was sunk by Washington (and SoDak). BUt with each of these examples, we can see that the precise labels did not matter. Hood was sunk, not because she was a battlecruiser, but because she was an unmodernized ship fighting a newer, larger opponent. Bretagne was hardly in a fair fight, just a fish in a barrel. And poor Kirishima was up against two ships that were newer, larger, and more powerful.
In fact, Fisher's vision for the battlecruiser was that it would eclipse the battleship or, perhaps more precisely, not "beat" the BB but "join" it. The modern dreadnoughts of post-1930 can all be seen as "fast battleships" or "armored battlecruisers," a BB-BC hybrid.
You know, it's hard to focus on Fisher's intentions and edicts; he made so many disparate statements at various times, I wouldn't be surprised if he once predicted the trawler would make the submarine obsolete. Dinghies are armor!
But I thought the Hood was sunk by a lucky shot from the Prinz Eugen ? In that case, if we consider the Kongo class to be "fast battleships", no battlecruiser ever was sunk by a battleship...
At Mers El Kébir, the French battleships managed to straddle the Hood twice before being knocked out of action. A hit on this highly vulnerable ship might have had momentous consequences. This daring and desperate action was a triumph for Churchill - it could easily have turned into a disaster. The destiny of nations sometimes hangs by a thread...