Very interesting! As I read through your request I had my response all ready for you... Then I read the 2 responses already given, and here goes...
My now 20 month old daughter had a tongue-tie as well. I was very fortunate to have this diagnosed by the time she was about 6 weeks old. Because she was over 4 weeks old, the ENT that we saw said that it had to be done in the OR under general. She ended up having it done around 8 weeks old or so. She was only under for 10 minutes total and it was a complete success. The surgeon said that she didn't have to cut much--I think 5 mm, but I could be remembering it wrong. It was a tiny snip and they were prepared for 2-3 stitches. She ended up getting one--and that was precautionary because there was absolutely no bleeding whatsoever. She was a little sore, but they allowed me to nurse her immediately following the surgery. What a HUGE difference in nursing. I know an older woman who is a nurse on a maternity ward and she said that years ago they would simply snip the tie in every single baby in the hospital--right away. There was never an issue. Once bottles/formula became so popular, that need decreased so dramatically that they stopped doing it as a routine procedure. Many babies, like myself, have been able to compensate for it for some reason, others--like yours and my little girl--still need the procedure. I experienced the same things that you have written about here (including not getting the tongue to the lips).
I didn't see where you live, but we went through the ENT department at CCMC. We used Dr. Murray--as she is one of the only dr's there who follow this school of thought. She was great--thoughtful, caring, clear to understand. We wouldn't go back and change a thing.
The above was my original reply. However, after having read the first response, it puts questions into my head. Are you still nursing? If so, I'd get it done as soon as you can. If not, now that he is 12 months old, would some type of a dental specialist be the way to go? Tongue-ties are hereditary. Can you find someone in your family or your husband's family with it? Does anyone remember having had it clipped? They may also be helpful in deciding whether to wait or not. My father-in-law had it clipped as a 6 year old. I can tell you that he said it was traumatic for him at THAT age--one reason we wanted it done as early as we could--but it had been interfering with his speech, so it needed to be done.
Feel free to contact me with any questions. I'm sure that I recorded some of it in her baby book, and I'm happy to share any and all of what I know/can recall.