in nature there is an ambiant light from the moon and stars.. as well as any passing cars.

i've shown the plants to people while they're asleep, no harm done. to make a change in the plants sex you need to be interupting the light cycle for prolonged period of time

often to get a female to turn hermie (as some people do want this)they'll have it on 12/12, but instead of 12 hours of continous darkness they'll turn it on for an hour each night for a week

so, to get a plant to turn hermie you have to have it on 12on/6off/1on/5off . have the plant on this light cycle for a week and she will grow a bunch of nuts ...BAM, hermie.

basically what it comes down to is this.. having a light on the plants for a few minutes to show a buddy.. is not going to do squat...