I don't think i need it that Frequently. The only fight where i can think i need to use it on CD for utility is Cho'gall. and then its on a 20 second CD not a 17. on AoE sure it's Great, but that's AoE and falls to the same logic that GoCleave does. On most boss fights you are in melee range of your target, I can't think which boss you need to tank at range. And if your lining up a burst you'd be saving shockwave, and of course if you wanted Maximal DPS you would STILL weave SW into the 4th GCD. since given our minimal baked in threat, Max TPS roation = Max DPS rotation too!
As for still having something to fill the fourth GCD I rarely find that CB, SW, HT are all on CD and i don't need to refresh either TC or Demo shout, or reapply a rend, But you can still use Dev or Rev to fill it, its just that proccing SNB only results in the next GCD having no rage cost.
Glyph of Heroic Throw saves you one GCD. Now if i didn't have the ability stack sunder quickly, like a fury or an arms warrior, then yes i can see the point, but as a prot warrior i don't even need to think about Sunder, if i'm on a target, it goes up. and as for Glyph of Sunder, Glyph of SW, TC and Cleave beat it in an AoE situation, its only really useful on fights where you're trying to kill two targets at once, in close proximity and most multi target fights its either full on AoE (Mal Green phase, Magmaw) or you keep the targets some distance apart (TAC, Nef) or you you're focusing down a single target (al'akir, ODS, Halfus)
- great due to adds: Magmaw OT, Maloriak, Nef, Halfus, Cho gall, Al Akir
- used very frequently due to being ranged and a lot of movement involved on Conclave (nature) and Council
- not particularly important but still very handy on Omni (slimes, stacked golems), Dragons (for a brief burst inside), glyphs not really needed here though
- on chim and artemedes its nothing special
HT not only saves gcd, its a small dps boost at the start. Its a lot more situational than SW, but still fantastic on Magmaw, Cho gall and Al Akir. And there is nothing better than it on many other fights anyway, ie Drakes, Council, etc. On ODS shields don't last forever.
Cleave is great on two fights - Halfus and Maloriak. Useless on the rest.