@OP, we have 1 dedicated DPS assigned to each leg (in our case, a Hunter and enhancement), and have a backup DPS to help us make bigger turns. When we need big turns, say for example right, we have the left leg guy switch to right as well with the backup. I don't see any better way than to have a driver call it out, if you have a ranged DPS assigned to driving, he/she might be able to have a better view of the whole platform if that's what you're wondering.
@Myrkur, Immolation does same damage no matter where you are (to be honest I wasn't aware of the 15 yard range). The main source of damage coming from the boss in P2 (not counting inactive volcano buff AND Superheated multipliers) is the stomps and the lasers. The Immolation just adds insult to injury
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