I certainly would never argue with someone who says they CAN feign submissiveness and enjoy it ONLY because it pleases their partner, but i have never met one or heard it second hand, or read about it on a discussion thread. That doesn't mean they dont exist. On the other hand, i have met and read and heard of people who can act dominant or learned how to be in order to please their partner. Some of them actually do not like it after all. Others like it because their partner likes it. But i have never heard someone who does not enjoy subbing or bottoming say they get vicarious enjoyment out of participating in that activity.
I realize i just repeated myself, but this is a touchy subject for people sometimes and i wanted to make sure it is understood that this is MY experience ONLY and is in no way a broad statement about all things everywhere.