I believe that I stated that in my experience it isn't necessary to re-educate a partner that their views of sex are wrong.
In the early days of our quad, there were some fights between Runic Wolf and myself over definitions. I already felt like I was making more than my fair of concessions; Pretty Lady and I are both masochists and Wendigo's superlong claws really brought that out in me during sex, but Pretty Lady asked that we not participate in any BDSM with each other in her presence and that Wendigo and I cut back on our use of the "L" word (NRE was a bit out of control in the beginning). As winter fell, one of our gaming friends found out his wife was cheating on him and refused to go home after game, cutting into the already limited amount of time that Wendigo and I had to reconnect physically and we were generally pretty worked up and ready to explode from our online conversations and from discretely petting each other under the game table on and off. (Our friends didn't know about us and most still don't.) So the later it got, the more desperate we got to get our hands on each other and we began formulating a plan; we'd find a spot on the country road between our houses and park behind the snow bank. For a few weeks, I'd talk to him and give him a hand job while driving to a safe spot, then we'd park and have sex and I'd drop him off at home. All while Runic Wolf was getting our friend to leave. Sometimes I'd come home and he'd still be there. One morning while I was taking a shower, Runic Wolf comes in and tells me he doesn't want me having sex with Wendigo in the car anymore. I agree, in part, because I don't want to risk our relationship further (Before I realized my feeling for Wendigo, I'd lied by omission and gotten caught, so we were still rebuilding trust). Still it was easy for me not to have sex with Wendigo in the car, because I could still give him blow jobs and hand jobs (or so I thought). But a few weeks after I'd agreed to stop having sex with him in the car, Runic Wolf was accusing me of lying to him about it. When we both calmed down, we realized our definitions of sex were different. For Runic Wolf, sex starts in that grey area that I consider foreplay; and is definitely when one or more person's genitals are exposed. We argued semantics for a little bit and then I asked him what was really at the root of it. He said that he didn't like driving to work the next morning with the car smelling like "sex" (arousal and sometimes cum). So we renegotiated over time. I'd stop having "sex" (by either definition) in the car as long as we arranged to not be sending Wendigo home more sexually frustrated than when he'd arrived at our house. Sometimes that meant that Wendigo and I didn't get to fool around at all that night, sometimes it meant hard capping when people left after game, and sometimes it meant staying up waay later than we intended, but we got though it w/o either of us having to change our definitions of sex AND by being respectful of each other's definitions.