Any doiecous plant is capable of sexual reversion.

It is a reaction to stress ( the plant essentially covers it's reproductive bets). Some strains, and individuals within strains, will show this reaction at lower stress levels than other strains, or individuals within the same strain.

Cannabis ranges from strains and individuals which will withstand incredible stress before reversal, to strains and individuals which will reverse due to stressors so minor that the grower wont even notice.

Think of it as an allergic reaction, though it's a flawed metaphor. The same little bit of pollen will make one person miserable, while another person doesn't even notice it.

The tendency to show this reaction is genetically mediated- much as members of the same family will often have similar allergies, or proclivity to cardiac disease, or what have you. Not every member of a given family will have hayfever, or a heart attack, or whatever.

And not having a history of allergies, or cardiac disorders, or whatever in your family doesn't disqualify you from developing hayfever or having a heart attack- it's a probability game. A history of expression of a genetically modified trait ( in this case tendency to gender reversal as a reaction to a particular stressor) in genetically close individuals increases the probability of the same expression in a particular individual in reaction to the same stressor.

A "stress-induced" hermaphrodite will tend to reinforce the probability of progeny expressing reversal in reaction to the same stress. If a plant expresses reversal under " ideal " conditions, either

A.) This individual has a very low threshold before reversal is triggered, or

B.) Conditions aren't all that ideal.

There will always be a triggering stressor that causes a plant to reverse, but very very often what that stressor is will never be identified. Much more practical to eliminate the abberant individual than to identify and rectify the stressor ( which may very well not trigger any other individual in the room).

'Course, if it happens a lot, you might want to either switch to genetics which are less likely to express this behavior, or figure out what the stressor is.