That's the same chart my group was looking at while practice but in the end we never use it. We just make it simple, split the group in half so 4 players would go each side, each side would have 2 dps 1 healer and 1 tank, we just pre-determined who going left and who going right.

Most death during practice happens because they are not sure where twintania is coming from or see it too late, so most of us will go to 3 o'clock or 9 o'clock depending if we are going left or right, half way there, turn to find twintania and make adjustment. When making adjustment we make sure we are not near each other, it's not necessary to always to stay at the edge after dodging the dive, can always move in a bit so that there are more space for megaflare.

If I saw someone going same direction as me when I am adjusting my position then I just called out like "BLM, stay there I will move". Just be smart about it, if someone is nearby then just move a bit. It's also one of the reason we don't set fix position like the chart, one person will always blame the other if get hit even though both of them could have just adjust their position. In the end dodging the megaflare after the dive it's all about adapting and making quick adjustment, if your position is 1 o'clock and someone is near you, just move and don't wait for the other to move, if using TS then just communicate.