For Heroic Spine specifically, reforge for Haste then Crit, not mastery like you are currently. Don't reforge into any expertise if you are having tendon dps issues as the tendon cannot dodge or parry. If you are good on tendon damage and have amalg damage issues, then reforge for expertise cap. The sub spec you had earlier is also fine for Heroic Spine. For glyphs, I would recommend Backstab, Shadow Dance, Slice and Dice and also use the 2 Pc T12 with 2 Pc T13 if you have access to the 391 T12 Tier. As far as a rotation for tendon dps, just make sure you refresh Recup and Slice and Dice right before the tendon pops. If you have any more questions, feel free to ask.