Its a nice method, not bullet proof, and it may not always work, but worth a try, as long as the water bowl does not shoot the humidity up, it shouldnt be a problem, just change the water daily as in a hot enviorment it gets nasty fast.

Beardedragon, Ive seen the maker of the video on a different forum, He has made changes to his set-up per the advice of others, and its better now, and along lines of the other great stuff people have. The vids a little over a year old i beleive. His current tank (larger), is a solid wood and im assumed moved. It is now fine, so dont worry about that.

Though dragons are hydrated through all methods, IMO they will drink if they have the need, they normally can not see standing water so associating it with a dropper, which is associating it with water, in a sense works theoretically. They also absorb water through there vents, and dropper and misting there head works good. There are many methods to a healthy happy dragon, It aint all black and white.

But he did come up with a relativly nice method, its worth consideration if you want to teach them to drink, Mine only drinks in his baths. Useful if you dont have the extra time to bath them as often.

Have a great day,
Ben