I'd estimate it was a group of about 10 who posted regularly to report on the effects ingesting cilantro. This was simply an active discussion followed by those of us with GD, nothing official and we all had differences in the amount or duration in our blended cilantro, a few tried the capsules (I did briefly to begin with and found no benefit, yet perhaps my dose wasn't enough, or perhaps something is lost during the processing).
I learned about cilantro following a Mayo discussion about GD, the usual discussion, participants desperate finding no prescriptions or doctor's able to provide relief.
Researching this would be an inexpensive study for a college, but it seems this disease, considered rare, generates little interest in the medical field. We're told it's usually transient, so just rub on an expensive worthless topical and put up with it and hope it goes dormant for a period of time. If you want to look it up, I believe it is still in the archives for GD discussion and as I mentioned it would be mid-February when Kimass1 enlightened us.
A study would find many willing to participate at no expense, the GD sufferers would gladly buy their own cilantro and report back to the study leader. What a great college project because most of us noticed results within a month.