The head bolts that need to be replaced are the torque-to-yield type. They are typically torqued in steps up to a certain torque, then an additional twist of 1/4 or 1/2 turn is added. They are stressed to material yield; if you looked at a used one, you"d see they are longer and smaller in diameter than an unused bolt. Using one a second time would break it.
They are used in specific applications; the only place I"ve seen them are on modern autos.
I"d think that head bolts on an A could be used forever as long as the threads are OK and aren"t corroded too bad or otherwise damaged.