Strange question

I started a calligraphy unit with my students. We use calligraphy markers and after practice, we use faux parchment.
One girl had used her pen to do her name in a "tagging" style.
I asked her to just use the marker for calligraphy and she claimed "This IS calligraphy."

What do you think? If done on small scale with a calligraphy point/nib on paper, could tagging be considered calligraphy?