I would agree with the first sentence, but the second one confuses me. How did you arrive at this justification for IEI-SLE pairs to be rare? Why would Result types not like each other? Is that some observation you have made, or where does this idea come from?
I believe Dual pairs are not that common in general, because most people tend to date a type that is more similar to their own in terms of strengths and weaknesses, as well as Jungian dichotomies.