I was wondering if the reason vis was so good was its been cold so not too many people in there stiring up, and not a lot of rain here lately.
Algae blooms have a much greater effect on the vis at CSSP than students do. I would put wind and rain as second and students in a distant third. Sure around Cisco, the plane, and the platforms vis is going to get crappy due to students. These are actual structures divers sit on, land on, kneel on etc and throw particles up in the water. The don't go very far though. In the rest of the pond, suspended algae is the cause of bad vis.
The reason (IMHO) vis stayed so good longer last year was all the rain we had in April and May. Not enough sun to trigger the huge algae blooms.
Now cold water prevents the algae from blooming. The particles are settling out due to a lack of high winds and vis is getting good.
Athens is much shallower and the students actually crash the bottom more often. The bottom composition is also different.
TwoBit