How much from the tie should be removed?
There is a lot of discussion about the definition and treatment of the different types of ties, and whether there is evidence that a treatment is effective and how much you have to remove from the ties.
Research in the past mostly looked at the most “obvious” and visible tongue tie that had a membrane to the tip of the tongue. But more recent studies by O’Callahan (2013) and Pranksy (2015) show that there is indeed a posterior part, behind the oral mucosa which also needs to be treated to alleviate the (breast) feeding problems. Sometimes there is no visible membrane under the tongue and a sub mucosal or “hidden” tie causes the problems with feeding.
Sometimes only the membrane is cut at the tip and the (hidden) part behind the oral mucosa is not released. An American ENT doctor describes it as if the sail is lowered on a sailing ship, but the mast is left to stand. See the blog (link) of ENT doctor Ghaheri.