SET MPRINT applies *ONLY* to what would be generated by MACROs.
SET PRINTBACK OFF will partially apply here (suppress LOG) but some commands will *STILL* be echoed to the Notes (these can be hidden, but not AFAIK completely eliminated without other intervention).
From our favorite fine manual:
" PRINTBACK refers to command printback in the log in the Viewer window and in the journal file. Syntax is always displayed as part of the Notes in the syntax window."
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