Funnily enough this never happens in practice because of boss phases and how you want a certain phase and want to lust away another.
Well on MSV, we lust at the beginning of fight 1, 3, 4. The other three have different phases (feng needs it in the last phase, p4 so, elegon at the end and at will of the emperor, nothing happens at the beginning of the fight.
On a patchwerk fight though, we always lust at the beginning, because all cds are ready, even trinket proccs line iup pretty well.
At least Explosive Shot interacts with another interesting mechanic. The random free procs make it a cool ability. Chimera Shot refreshes Serpent Sting but... that's boring. It should have the old Serpent Sting component back.
Arcane also has random free proccs if specced TotH, its nearly the same thing :-)
In pvp chimera has the interesting ability to slow, which is about the only advantage a MM gets for pvp
The buff to CA is trivial at best....the first 20% of boss health doesn't matter on normals and is even less important on heroic bosses. It's nothing more than a tool to prop up/inflate dps. Blizzard keeps dancing around the fact that they need to fix the DAMAGE of MM spec before anyone will take it seriously. Steady is weak, chimera is weak, and the steady focus buff mechanic is cumbersome and outdated. I hope they put some serious changes on the table in the next major patch. It doesn't look like we're going to get anymore than scraps in 5.1.