But see, it works both ways. If a judge can unilaterally block the president from exceeding his authority, a judge can equally well block the president from exercising his authority. (There is no magic black letter printing on executive orders that is within his authority and red letter printing for those that exceed it. In fact, this is exactly what these court cases are about.)

So either a judge can block orders that exceed the president's authority and orders that are within it, or the judge can block neither.