Perhaps it was not clear, but a good portion of them couldn't orgasm vaginally at all.
Even those who could, required manual stimulation while having intercourse that's only 1/3 of that 1/2.
I'm sure my experience isn't representative (as any one person's experience is hard to extrapolate as representative), but still that's a good many women running around not having vaginal orgasms.
I would hesitate to believe that there are that many defective women running around. In other words, it seems to be well within the normal range of women's responsiveness to penile insertion alone. That may not make you feel better about it. But, it's not an operational defect even if still disappointing. This, in essence, was my point.
Male, Straight, Poly
“Instead of getting better and better at avoiding, learn to accept the present moment as if you had invited it. And work with it instead of against it. And making it your ally rather than your enemy.”