I think you are still confusing mils and milimeters. I don't know off the top of my head how thick 10 mils would be, but I would guess somewhere in the neighborhood of .020" - .030" or twenty to thirty thousandths of an inch (as a reference, .125" or one-hundred twenty-five thousandths is 1/8"). from what I gather on the website you've linked to, the 'mils' measurements are refering solely to the thickness of the backing material. the thickness of the wood is probably somewhere in the neighborhood of 1/16" to 1/8".
veneers are very thin sheets or strips of wood (or porcelain in the case of teeth) that are meant to be applied to a thicker material. their purpose is to give the appearance and finish of much more expensive woods without the cost of using solid materials.
a good example of this is the cheap assembly required furniture at Wal-Mart or any other department store. It's base construction is of pine, ash, partical board, or some other reasonably cheap (usually softer) wood. It then has a very thin hardwood veneer applied over it that will have a more attractive grain and can be finished to look better.
In short, both the 10 and 22.2 mil veneers are going to be nearly identical in thickness. Most likely only about .030" difference overall.
I hope this helps. If not, let me know and I'll pm my digits and I might be able to better explain it over the phone.
Best of luck!
