I have been privy to an ongoing discussion about the British battlecruiser losses at Jutland. Frank Fox is definitely in the camp that blames the losses on Cordite being fundamentally unstable and poor handling procedures. I have put David K. Brown into this camp, as well, although I may be mistaken. In The Grand Fleet, he addresses this problem, as well.
There is an alternate theory, which wants to blame Lyddite shells for the losses.
There is an interesting case from Jutland, where the battlecruiser Tiger received a hit on Q turret, but not only did not explode, but the guns were back in action after "a short time". The X turret barbette 9in armor was also penetrated, but again, the Tiger did not explode.
The Lion was almost lost due to a Cordite fire, after the Q turret hit. DK Brown thought that the ship was only saved due to the magazine flooding.
The Invincible was lost due to the hit on Q turret.
The dangers were perceived to be threefold:
- poor quality in manufacture of Cordite
- old Cordite would become unstable, and it was retained for too long
- exposed igniter charges (but this may not really have been a factor)
The conventional wisdom, circa 1917, was that the deck and side armor was too thin. This really was not the issue. Instead, there was the inherent instability of Cordite and poor handling practices in the battlecruiser fleet (except where they were corrected on the Lion by Chief Gunner Grant).