My late grandfather used to teach some classes many years ago.

He recounted how one time, after he had graded and handed back some deliveries from the students, one of them came up to him with a confused look on his face.

The student said: In the feedback you wrote D.N.A.S.M. What does that mean?

My grandfather said: It means Do Not Abbreviate So Much.

Your comment reminded me of this :)