Crazing in glazes is common in this type of ware but since the body is fired well into vitrification this is not considered a problem (the unique aesthetics of this type of ware trump such issues). Salt glazes, by their very nature, are high in sodium. Since Na2O has such high thermal expansion pieces are almost guaranteed to craze. This was from kiln at the Medalta artist in residence program
Salt firing is a process where unglazed ware is fired to high temperatures and salt is introduced to produce a vapor that glazes the ware.
Ask the right questions to analyse the real cause of glaze crazing. Do not just treat the symptoms, the real cause is thermal expansion mismatch with the body.