Last night I stayed up late and took part in Sanctum of Rall downing Tequatl the Sunless. The fight is really fun and challenging. It's great to see something raid like come into Guild Wars 2. There is one huge glaring flaw though, which I'll get to in a minute.
The strategy used was to form a dps zerg on one commander right at the dragon's feet. Everyone in this party used Powerful Potions of Undead Slaying. All the guardians went staff for empower and swapped scepter for head shots. Their job is to kill fingers, revive comrades and dps the dragon. And also, dodge waves.
Then we had two turret groups. It doesn't take a lot of skill to man the turrets but it does take someone who can pay attention. It's very easy to lose focus of skill 2 and also lose your target because the Tequatl fingers pop up and steal it. We ran with roughly 20 people in each turrent defending group. The objective is to keep mobs and fingers away from the turrets so those players can do their job.
I was part of the "south" turret team which is really more easterly than south, but that's what everyone is calling it. I ran a standard grenade build with a mix of zerker and invader gear. I'd say it worked out really well for my role. If I had been in the zerg I would have taken less zerker gear. Without toughness and vitality one missed wave can take you down.
If everyone does their job then you will see the megalaser phase. Everyone needs to get back and protect them, but once you know none of them are going down, like with 20 seconds remaining, send the zerg back to Tequatl's point to kill fingers. You should be able to kill all of them before he arrives and you get full focused dps, including the turret defenders until they are needed back north.
Rinse repeat this and you should see a death of a dragon.
The main flaw I see is that this will be rarely done 6 weeks from now. It takes over one hundred coordinated people to do this. Everyone is all fired up about it now but after a few kills or after they get their wings they won't be back.
I love the challenge and I think Jormag and the Shatterer are too easy. But they still get killed almost every time they spawn and it's been over a year. I don't see that happening when something requires this many people and is also this hard. I hope I'm wrong but I just can't see that.
Arena.net has a very tough job of figuring out how to make something challenging with a few people and with tons of people. Maybe it's just tweaking the auto scaling, but I haven't seen that work. Everything in the game until Tequatl has been easily overpowered with a huge zerg. This one might go too far. Time will tell.
If my theory is right and you want to make some coin, you should see all of the Tequatl drops like minis increase dramatically in price over the next three months. The dragon is dying often right now and people are flooding the market. But those will sell and then there won't be any supply. Don't hold me liable come December if you stock up on them now and lose money, but that's what I think will happen.