I have wondered about that, too?....a little experiment I did this winter;..I set my new T-5 lights on one side...while under a 400 watt HID light...and the plants would bend toward the side lights...????

I can't help but think that if you surround plants in fluoros...it will have an effect....

They would have to be the strongest fluoro tubes, available..:wtf:....$$$$$