Meh I don't buy it, the method of the study seems not very sound. I myself was on a 10 days meditation retreat http://www.sobhana.dhamma.org/ where we meditated for 16 hours a day or something and sure it helped with the mood, relaxation, etc. but it wore out after a couple of weeks and I never had the nerv to meditate daily because it was not worth it. Btw. my brother and sister attended it too and both say the same about it.
I did it "daily" for 10 days very intensive, and the bliss or what you want to call it was there but not worth the hassle. But I also have a suspection that I'm the wrong person for that because my normal level of being is already very calm and relaxed. The only thing which can get to me if I don't sleep enough.
