How to play DW Survival, or why isn't it working for me?

I play a Hunter-Survivalist, and I've had many ups and downs. I never wanted to play like Rexxar, and I liked his two-handed approach.

However, times have changed, and now Survival mode not only allows dual wielding, but has become a viable way to play, at least according to guides and logs. Mostly, everyone uses daggers and corresponding talent builds.

But whenever I try to use a two-handed weapon, it's like hitting someone with two wet noodles. Even a simulation using Raidbots on a single target shows worse results for two-handed weapons. At item level 265, I get about 80k DPS with a two-handed weapon, while the simulation shows about 1500 DPS less for two-handed weapons.

I just finished Dreamrift in HC mode (with a few wipes), and it was really hard with two-handed weapons, while my trusty two-handed weapon was fine. What am I missing?