An interesting historical note is that one of the strong objections to machine matzos (by those who assured) was for round machine matzos. They corners are trimmed off and the trimmings are added back to be rolled gain into matzos. There was a problem because the “shehiyos” are miztaref. There was a lesser problem with square machine matzos.
Presumably, the inverse problem would be with square hand matzos, they would have to be squared off, do you think they would discard such a large amount of dough? It would be rolled back into the dough and there would be a problem of “sheyioh”