I am not sure about vita shell but I agree the test should have been longerTom, you know I have lots of respect for your work with Tortoises!
BUT..
You only did your ran your experiment for 3 months. I don't think that is nearly long enough to come to a proper conclusion! I know that the growth rate of Hatchlings can be pretty dramatic but Vita-Shell is not a Quick Fix kinda product.
Now, if you ran it for the 2 years that you think hatchling should be in a Hot/Humid conditions (during the formative years of their inner shell) THEN you would have a solid foundation to claim it makes no difference.
You never gave Vita-Shell a true test. You used one container on several Torts and call your experiment good. Wich is really kinda sad because you do so much good for the Tortoise Community but did a half-assed experiment with this one product. People take your word as "The Standard" when raising torts and when you "poopoo" a product because "You did a side by side experiment", well, it really becomes "LAW" in the eyes of most who raise torts.
That's all I have....