Yep, this is the reason. The same reason they use 'q', 'c' and 'x' etc., they don't correspond to English, or Italian pronunciation of those letters. They are

Yep, this is the reason. The same reason they use 'q', 'c' and 'x' etc., they don't correspond to English, or Italian pronunciation of those letters. They are "pronunciation keys" and Wade-Giles was the same. Just represented differently.