I can't see anything that the dive op did wrong compared to other locations. Having a meth-head boat pilot was the first problem I think as he should have followed their bubbles better and been on the lookout, but I've seen failures elsewhere. I'd like to know if the instructor had and tried an SMB, but I'd also encourage all DMs to carry a signal mirror, Storm whistle, and reg whistle. Reg whistles are the loudest, but if out of air, Storm whistles are rather loud. Drifting divers happen tho, and I still think it's important to keep the group tied together, like reg hoses tied to D-rings. Maybe her heroic attempt to try to swim for help was a good idea, but I'm against breaking from the group.