The Frierdiker Rebbe (1880 – 1950) once said regarding why Lubavitcher Bochurim don’t wear a Gartel over their jacket, (we do wear one before marriage, but under the shirt) “מיינע בחורים זיינען נישט פסול’ע ספרי תורה” – My Bochurim aren’t Posul Sifrei Torah.
Implying that married men are?