I have seen a lot of people talk about their issues with getting Sarth3D. While I have done it 5 times now it is by no means a one shot. The fight is about more than just stats and skill. You have to get past the random factors. I have seen a lava strikes take out four players in the mater of seconds. I have seen anything from a very few adds spawn to so many I could not even see the add tank. Face it the difference between a shiny new mount and a wipe could be one lava wall placement.
I have two benchmarks on how I gage how well an attempt is going.
Did we kill the first drake before or within five seconds of the second one landing?
Did anyone die by the time the third drake land?
We changed one small thing and since then we have killed the first drake every time before the second one lands. Any player that uses a chance on cast trinket simply did not do any DPS until the first drake landed. Why proc your trinket with a 45 second cool down when you need to kill a target in the next 55 Seconds?
A lot random things can kill players during the fight. Many can be avoided but some times an add spawns and will hit a healer at the same time a lava strike comes down. Goodbye healer. We got pretty good at not standing in the red circle I think we had more trouble since they changed the color to blue. When I see blue scroll up from my feet I just think I am getting some manna. It took a few tries before I finally started to run out of it without having to think.
Doing 2 Drakes up should be very easy for your guild. If you can get to the point that 2 Drakes feel almost boring then you are ready for 3 Drakes. No reason to even try it more than a few times if you have not done 2 Drakes up. If your players have to think about where to move for lava walls or when it is time to aoe adds then you will not be ready for 3 Drakes.