You can make an auto flowering cutting grow roots, but it will grow at the same rate as the host plant. If you take a clone from a 3 week old AF......the clone will begin at 3 weeks and finish at the same time as the mother. It might end up as a 2 or 3 gram bud at best. Auto flowers have a distinct lifespan that is not determined by light cycles but rather by genetics. Autoflowers need to be grown from seed to maturity.