Why do some groups still use the ABC setup for Echidna?

[MXMoondoggie]

That is, the set up that puts the snakes within 90 degrees of each other meaning they have 2 stacks of the buff and can potentially two-shot inattentive derps like me with their shockwave attacks?

I'll own up to standing between them being my fault, but what's wrong with the BAC setup that has Echidna at the north and the snakes on opposite ends of the arena?

People just create an accepted way of doing things and that's how it's done in DF it's the simplest way to get people to understand their positioning. It's like all the other raids it was easier to just use the same spots for everyone even if sometimes people still don't understand where they are supposed to go. In your case you are just standing too far away from your groups snake. Just get on it's snakey butt and the other one won't reach you.