Wow, that's great that it's working so well. We might have to try that too. DS2 is 2 and also a big thumb sucker, although so far the dentist has told us not to worry about it as it's not doing any damage (I think it depends on the position of the thumb in the mouth or something?). But it would be great to have him stop and not have to worry about it. I'll be interested to see if it is as easy for you as it seems like it will be.