Actually, Fisher's original concept was to abolish battleships totally:
This review says it all, from Amazon:
"In "Sir John Fisher's Naval Revolution" Nicholas Lambert has provided a comprehensive analysis of the policies of Admiral Sir John Fisher and the Royal Navy in the ten years before the outbreak of World War One.
Lambert makes it clear that Fisher was not appointed First Sea Lord in 1904 to introduce the dreadnought battleship/battlecruiser but to cut naval spending. This fact spurred Fisher to introduce new technologies to maintain Britain's naval supremacy when that supremacy was increasingly under threat from a number of quarters. Lambert puts emphasis on Fisher's ideas about the use of flotilla craft. These were small submersible boats and surface craft armed with torpedoes that could close the narrow seas around the British Isles to enemy battle fleets thus freeing the British fleet to roam the high seas, bringing battle to the enemy and protecting her own huge ocean trade. Lambert shows how on the eve of the war, the Royal Navy was on the verge of stopping battleship construction altogether on favor of flotilla craft. This is new ground."
The whole point of BCs was act as cruiser-killers on a global basis, protecting the Imperial trade-routes. Home defence was to be the responsibility of torpedo-boats and submarines, not battleships....Fisher never liked them. His favourite ship when a sea captain/admiral was the Renown...a light. fast (for the time) battleship.
Here's the same thing on wiki:
http://en.wikipedia.org/wiki/John_Fisher,_1st_Baron_Fisher" Fisher's policy with regards to Dreadnoughts has often been misunderstood; it was not a class of ship which he favoured, as his time as admiral of the Mediterranean fleet had taught him the vulnerability of slow big gun ships to mines, torpedoes and submarines. He wanted battlecruisers to defend Britain’s colonies, and a large fleet of small ships to defend the British Isles. However, when his plans for battlecruisers met with opposition from within the service, he was forced to compromise. "
So the BCs were, from the time Fisher's concept was hi-jacked, forced into a role never intended.
Re the Hood...her protection was actually as good as the Queen Elizabeths and the cause of her sinking is still uncertain today. It is suspected however that a fire in a secondary battery caused by 8 inch shell from the Prinz Eugen flashed to a magazine and caused the explosion.
As a point of interest, exactly the same thing happened to make the Yamato explode...
wiki again:
http://en.wikipedia.org/wiki/Japanese_battleship_Yamato"The first two bombs dropped by Lt. Commander Wood hit on the starboard side of the weather deck, knocking out several of the 25 mm machine guns and the high-angle gun turret and ripping a hole in the flying deck. Seconds later came the two bombs from Lt. (jg) Ferry, destroying secondary battery fire control station as they blew through the flying deck and starting a fire, which was never extinguished. This fire continued to spread and is believed to have caused the explosion of the main ammunition magazine as the Yamato capsized some two hours later. Hot on Ferry's tail was Lt. (jg) Sieber, delivering two bomb hits forward of the island, ripping more holes in the decks in the vicinity of the number three main gun turret.
The torpedo plane pilots were ordered to aim for the unarmoured parts of the Yamato's hull; the bow and stern. They were also told to only attack her on one side, so that she would capsize. Within minutes of the Helldivers' bombing, the Yamato suffered three torpedo hits to her port side and began listing.
Over the next two hours, two more attacks would be launched, pounding the Yamato with torpedoes and bombs. Attempts of counter-flooding failed, and shortly after 1400 hours, the commanding officer gave the word to prepare to abandon ship. As the ship listed beyond a 90-degree angle and began sinking, a gigantic explosion of the stern ammunition magazines tore the ship apart. The huge mushroom of fire and smoke exploded almost four miles into the air and the fire was seen by sentries 125 miles away in Kagoshima prefecture on Kyushu, the southernmost of Japan's four main islands."
"The senior surviving bridge officer Mitsuru Yoshida claims that a fire alert for the magazine of the forward superfiring 155 mm guns was observed as the ship sank. This fire appears to have detonated the shell propellant stored as the ship rolled over, which in turn set off the magazine in turret 'B' resulting in the famous pictures of the actual explosion and subsequent smoke column photographed by US aircraft (shown above and recorded as being seen in southern Japan, one hundred miles away).
The bow section landed upright, with the stern section remaining keel up. The three main turrets fell away as the ship turned turtle and landed in the wreckage field around the separated hull pieces.
A further large hole was found in the stern section, strongly suggesting that a third magazine explosion occurred, possibly the aft 155 mm gun magazine.
Further examples of capital ships being lost due to magazine detonations of this nature during or after battle are the British battlecruisers HMS Queen Mary, Invincible and Indefatigable at the battle of Jutland in 1916, Hood at battle of the Denmark Strait in 1941, USS Arizona at Pearl Harbor in 1941 and HMS Barham in the Eastern Mediterranean in 1941."