48 hrs of darkness b4 harvest... is this true for autos too?

ok so i keep hearing that you should treat your plants to 48hrs of darkness before you harvest. is this true with autos also? would it help anything or is this something that simply doesn't apply to autos?

alright fella i dont know the answer to that one but im growin autos aswell wot ones are you growin?

i am starting my first grow with purple ryder seeds from the joint doctor.... as soon as the holiday weekend is over i am making another order to the attitude to get some himalayin blue diesel, stuporsonic, onyx and blackberry seeds. the blackberry isn't an auto but i can't help it... it looks soo good.

what are you growing?

nobody knows if this is a good thing or a bad thing?

i let mine sit in darkness 24 hours but i don't think it would hurt to go longer