If you have to force a female to give pollen, it isn't a natural hermaphrodite.

Every cannabis seed and clone you will ever come across will have this ability to one extreme to the other. It is a thought to be a self-preservation technique for the species, not a genetic malfunction. Stress induces the trait, but some strains have a lower tolerance to stress, and hermie easier. Some can be rightly abused and still remain celibate. Likely bad breeding practices damaged some strains making them more hermie-prone.

By the way...this ability for the female to make pollen, is the only reason there are such things as "femmed" seeds.