That's all understood, but it isn't what's been done on one animal. As far as beardies, yeah, it's only been used on some animals, but the results are enough for me to say it's a better way of keeping them. With uros, the soil and high temperatures have been tested on many individuals, and on breeding groups at pro exotics, who have grown to adult size in about 1/3rd the time it usually takes in a captive environment, and they have also reached sexual maturity and began breeding at about the same time (I'm hoping that soon we will see if the breeding was successful). As you must know, uro's are very hard to breed, and I think that's because we're not really giving them the appropriate conditions to live in.
It's just like with monitors. Years ago people thought that keeping them on paper and giving them low hotspots they were keeping them right, and they couldn't find out why they weren't as healthy as they should be. Then people began experimenting with burrowable dirt substrates and high basking temperatures and those methods have proven to be the best at raising most monitors (terrestrial in nature). It's these people that started experimenting with similar setups for their other reptiles, and these people that have been having greater success (meaning no parasite problems or impaction problems, even though they're feeding off a particulate substrate).
I think in this forum I do a good job at stating that it's speculation. In the uro forum I don't, because it has basically already been proven that they do much better in captivity when given the same or similar resources that they would get in the wild.
I'm just trying to help people on these boards, because time after time I see people constantly having problems with parasites and constipation, and this has to do with the way they are keeping them. As a reptile keeper, I realize that most people aren't going to stray from what their books say they should do, but I think that's a handicap more than anything. It's the duty of reptile owners to be able to make decisions that could push the hobby along and make for happier healthier animals. So far, since I've started using these methods, my once sickly dragon has been acting 100% healthy and about 10 times happier. The same goes for my uro, and the more and more I talk to people that are trying these things, the more and more I find that they have the same results.