As I mention in the description, it's probably best to stick to Silencing Shot method if you have competition, as otherwise the tame may be made while you're off getting the buff. Personally I stand on the buff rock and Eagle Eye the other spawn points.
From the video description:
How to quickly and easily tame Karkin/Skarr, no MM spec, haste buffs or potions/elixirs required.
If you have lots of competition, it's probably better to stick to the standard tame tactics, as someone else will probably get the tame while you are getting the buff. You can camp on the buff rock (it doesn't disappear) while Eagle Eyeing the other spawn point.
* Just past the normal rock-jumping route up to Fireplume Peak, there's a second rock you can jump up with using an Updraft. This Updraft gives you a 100% haste buff called Convalescence of Winds.
* Pull Karkin/Skarr with a shot to tag or with just Tame Beast to trigger Fieroclast Barrage. WAIT until the Barrage is near completion, and then Deterrance and Tame Beast again.