Thing is, it’s just not true. 3-MMC spins you up hard and it would be extremely obvious in a work setting, for example. These are just the words of a user that wants to believe that no one knows when they’re using.
Not that I recommend being on 3-MMC at work, but it's just a matter of dosage. People take pharmaceutical doses of Adderall at work and 10x higher recreational doses at clubs.