Dymphna's active clients do recommend her programs, but I presume that your point is why can't I find them in the forums ?
Most meet face to face and don't join public forums, cause they network inside the group and in insider forums.
I met her students at third party events as well as her own events. She had about 75 students in the VIP lounge last time I attended, which was 6 weeks ago. Having said that normal distribution suggests that the majority of seminar attendees do actually very little with the content any seminar. You didn't say what sort of investment model you are after ? Maybe you prefer the Reno Queen Cherie Barber, she has signed about 1500 students(2010)and has a very high media profile.
She was just on public TV last week.