Ehm, I think 50% torpedos was attracted by CMs and from those 100% detonated on them. So it's rather 50% * 100%
100% detonation of 50% successful torpedo attractions, so 1/2 of the times a CM was used against a torpedo it destroyed
in theory, because I did not statistic research on this phenomena
, but I didn't ever see a torpedo that hit a CM and not detonated
