I have enjoyed reading this thread, very interesting. I have wanted to try this method as I've heard good things. I have naturally frizzy hair and have recently discovered its the sulphates in the shampoo. I don't hair straighten anymore so have been experimenting with ways to keep the frizz down. Conditioner only worked a treat for me but after a few weeks I noticed an increase in shedding (so not for people prone to hair loss). Apparently it loosens the hair shaft. I found a great sulphate free shampoo in the Bodyshop (Rainforest) which was fantastic but expensive. I tried diluting sulphate shampoo which works a bit. I'm now on son of morris savers baby shampoo (11p) I still get a tiny bit of frizz but massively reduced.
Another great find is a generic brand of dry shampoo from H"bargains (74p). I usually use Batiste on my fringe but have turned to this cheap version which is better because it has such a fine spray
I'm thinking this summer might be a great time to try this no shampoo business