I think I understand what your saying. And that is truly possible. Tongues are used for various things. I think the many times it is an angelic language that isn't necessarily an interpretable language from a certain "people group". Mainly a prayer language to God, which is between the prayer and God. And if it is a message for all to hear, it will be spoken so all can hear, then someone with the gift of interpretation will interpret.
I know of some instances that God gave a language to people who knew nothing of that language, but when it was heard by a bystander, that message was for him/her in their own language. Although the speaker has no idea what he/she said.
