laskern,
Tefilin on chol hamoed cannot be baal tosif. Baal tosif is to wear 5 parshiyos, or 5 minim in the lulav, sukkah on simchas torah (Avi K – in chutz laaretz) because of 8 days instead of 7, etc. If you say shema before davening because of the zeman, and then say shema again during the zeman, tht’s not baal tosif either.
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