I checked "No, it is not heresy."
Differences on the nature of tongues and their application to the life of a believer are difference in doctrine, not foundational belief.
I apply the term "heresy" in a strict way. Given that ecstatic experiences existed throughout the early church (including the apostolic age) I do not generally believe that teachings on the use and application of a doctrine of miraculous gifts is (within reason) close to heretical teaching. It is a doctrinal difference. We must do doctrinal triage, supporting the foundational, doctrinal, and preferential. Not everything is foundational.
Differences on the nature of tongues and their application to the life of a believer are difference in doctrine, not foundational belief.
I apply the term "heresy" in a strict way. Given that ecstatic experiences existed throughout the early church (including the apostolic age) I do not generally believe that teachings on the use and application of a doctrine of miraculous gifts is (within reason) close to heretical teaching. It is a doctrinal difference. We must do doctrinal triage, supporting the foundational, doctrinal, and preferential. Not everything is foundational.