When people bring this kind of thing up, my first thought is generally that they don't know enough people.
Yes, there are definitely s/s couples out there, though I do agree with the article that you don't see as many s/s couples as D/D ones. Of course, that leads to the difference between actual s/s couples, rather than those couples who will service top each other vrs those that are actually switch/sub couples (those who spend periods of time where one will take the Dominant role for the other) and switch/switch couples (those that take turns taking the Dominant role for each other).
Some of this really depends on the people. If neither partner is interested in topping or Dominating the other, there is always the outlet of poly *if* the BDSM/kink/D/s thing is high enough on the priority scale, though some don't find the idea of a primary relationship that automatically necessitates a third party to be fulfilling. If those things are on the lower end of the scale, they tend to be more interested in the other aspects of life with a fulfilling partner, and the kink part isn't that big of a deal.
However, I do have to say that, of the s/s couples I've encountered, most of them didn't set out to be s/s couples. They were people who got into kink after the relationship had formed or they are in arrangements that were specifically not what they were seeking originally. I don't currently know any submissive women that are specifically seeking submissive men, though some submissive men think this is a great idea for submissive women to get their wants met. (The trading off idea.) There are also some submissive/bottom men that think teaming up with a submissive woman to be able to offer themselves as a 'submissive couple' will bring them better results. Usually, the submissive woman will find a poly situation long before the submissive man, and the Dominant or D/D couple will be only interested in the woman of the couple.
The crowned Diva of Destruction. ~ ExT
Beach Ball Sized Lady Nuts. ~ TWD
Happily dating a new submissive. It's official. I've named him engie.
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