Reply To: Putting on Tefilin on Chal Hamoed

The sefer haminhagim brings an implication to put on tefillin on chol hamoed. If you take the pasuk about tefillin שם ה נקרא has the beginning letters שין indicating that there are 300 days in the year when you put on tefillin. If you remove from 365, 52 shabbosim and 13 holidays (4 pesach, 2 shavuos, 2 rosh hashonoh, 4 sukkas, 1 yom kippur) we get exactly 300 days when we put on tefillin.