This is not, as far as I can tell, an example of “a minhag brecht a din”, which is not true. The mitzvah of tztzis is not chiyuvis, so the minhag can legitimately determine when one should be mechayev oneself by wearing daled kanfos.
This is not, as far as I can tell, an example of “a minhag brecht a din”, which is not true. The mitzvah of tztzis is not chiyuvis, so the minhag can legitimately determine when one should be mechayev oneself by wearing daled kanfos.