Actually, I was making a bit of a joke about the numbers thing:-) So much is lost in the translation...
I did say I think consistency is good, just that I haven't seen any evidence of it yet. There's Bob's way (which you're following), and various others, but no wide agreement on which is best.
I'm not sure I agree regarding subcutaneous implantation, etc. If it is between the dermis and the muscle tissue, there is no reason for the tag to be lost through shedding. Injury, perhaps. Maybe the problem with this is that some people don't actually get it deep enough. I've seen snakes with tags in the field that had persisted for 6-8 years, and I'm sure there have been longer records. The researchers have put a lot of effort into figuring out the best ways to do this and they want the tags to last for the life of the snake. I can see intramuscular working as well. I don't think I'd want to be implanting into the body cavity proper (as in inside the ribs) as there are lots of vital parts in there and it is difficult to know what you might hit. Are you really putting them within the peritoneal membrane? I would consider this to be way more invasive, and a surgical procedure which should be done by a vet. To me the risks would outweigh the benefit of not having the chip be noticeable. Just my opinions, of course, and I welcome the discussion, as I will be investing in a reader and implantation kit this year- we have more snakes of our own to do now, and presumably lots more in the future.