I'm thinking that this has some real validity to it. Besides, the 24 hour a day thing really eats up electricity, and if it's true that the plants can only take up so much light after a point, then that rest period is pretty important - if only to allow the plant to regain its strength for taking in the next dose.
I did 24/0 the first time and I was happy with the ratio of female to male (though I would have preferred all "ladies"), so I don't think lighting has much to do with gender switching.
I'd be more inclined to attribute that to stress on the plant, but I'm still reading on it.
LG
