Cannabis doesnt need a "rest" there just comes a point where it cant use anymore light. Again, this is fact. It is called "light saturation". It is bad for plants.
http://www.maximumyield.com/asktheexperts/item/38-photosynthesis-maximized
The only reference to "too much" light refered in the article above, states,
Having too much light for photosynthesis can occur in indoor gardens as well—more commonly with younger plants or with those that have been grown under lower light and then planted out under a greater light intensity. Very high light intensities will break down chlorophyll, imparting a white, bleached appearance to the leaves and resulting in a decreased ability to carry out photosynthesis.
We all know if you are bleaching your leaves, the plant is saturated with too much light.
If you read my post on page 2 it says within the pages of the book that "No problems are attributed to the plant at a 24/0 light schedule".
So, in theory, according to the link you inserted, if Im not bleaching my leaves at a 24/0 light period then my plants are still not being overly saturated with light.
Just a healthy debate, im not trying to take shots at anyone so dont take it the wrong way....It was a good read nonetheless!