I'm a blood DK myself with the build 51/0/20 and I just don't understand why I keep seing so many blood dk's skipping hysteria. I mean first I thought 'maybe they don't know they can buff themselves' and I actually asked one, and he told me he thought it was a completely useless talent.
My obvious questios is - why? 20% damage increase for 30 seconds? How is this useless? Yes, it has a pretty nasty debuff, specially for pvp, but come on. In a group you'll generally always end up being healed through it so... can someone enlighten me to how hysteria is useless?