Another point to consider. Some submissives attempt to "top from the bottom". They say they are giving control over, then want to direct you on what to do to them.
I would also like to add, that talking about it is always an option. The sub may feel like their actions where the "Way it's suppose to be". In my opinion if your not willing to have open and frank discussions about your expectations, hard and soft limits, or fantasies then any form of BDSM could be dangerous.