I was wondering, would playing with lights in veg affect the plants? Switching from 24 hours to 18/6 or even going from running 2 down to 1? I really have no idea? You wouldn't think so huh?
If I had vegging plants that had "heat or light stress" leaves...I would do something...right or wrong.

UV light from MH bulbs is very tricky. (just stick your hand under the light for 5 minutes...then you will feel their pain)