Hi DOGGBONES --
I hope you mean someone else 
...but I don't think there's anyone else named Bruce here...or would admit to it!
Dr. Koufman has success treating SOME of her patients with her diet, but I don't think even she understands why some respond and some don't. There is another forum member here, PPI-LESS, who went to her, and I believe had no success.
I once tried to start a thread here about defining GERD, but it wasn't met with much enthusiasm. The reason I wrote this other thread wasn't to be a know-it-all, or exclude members, but to encourage folks to really take a look at their symptoms, because it is within our symptoms that we can find the source of our individual issues. You can find a couple of different definitions of GERD on the Internet. One, a global "catch-all" that just lumps excessive reflux into the definition, and another, that relates it to a weak LES. Most doctors subscribe to the latter, because they recognize that there are other reasons for reflux beyond a mechanical one. It's unfortunate that many folks self-diagnose themselves as GERD patients, and skew their treatments towards this malfunction with limited success, when in fact they may have better served themselves by seeking a cause elsewhere.
Enter Dr. Koufman. IMO, I think a dietary approach to reflux is most helpful in those patients who also have gastritis, poor digestion, gas, and perhaps stomach emptying issues. This because the reflux, in these instances, is probably more related to excessive stomach churning, gas pressure, and even nausea pushing stomach contents upwards. In these cases, it doesn't matter how strong/weak the LES is, if there's a force pushing the reflux, or a subconscious physiological response to evacuate the stomach, it's going to pass the z-line.
As far as pepsin goes, it's a destructive thing whenever it escapes the stomach and finds its way into the airway. There's no question about this. But, again, IMO, this is academic. To a researcher, it's important, because it leads to a better understanding of human physiology. To this effect, there may be papers written on it, that are available for viewing on the web. Doctors are often rushed, and don't talk to us like they should when we visit their offices, which forces us to search for our answers on this great tool in front of us on our desks. However, we sometimes aren't able to separate the "wheat from the chaff" very well with such an overload of differing ideas (and to be frank, snake oil salesman too), so that it's very easy to get confused, overwhelmed, and even delay further treatment because we read about someone recommending us to "try this." Been there.
To folks suffering from reflux, it's more important to search for the root cause, and not the separate mechanism of the symptoms. Is it acid, bile, or pepsin burning your throat? Does it really matter? It would matter if you are one of the patients that Dr. Koufman's diet helps, because your root cause may not be a weak LES, but more of a digestion issue.
But how do you tell the difference? Medical tests like pH (impedence or Bravo), manometry, and barium swallow would determine esophageal issues with respect to reflux. But more simply, you can self-evaluate, too. Is your stomach churning, bubbling, aching, hurting, etc.? I can't emphasize enough how we need to become our own advocates, learn as much as we can, and pay attention to our symptoms. No one else will do this for us, and we should NEVER put all our faith into our doctors. A doctor has to PROVE to us his competency with his evaluations, care, and even patience...not for us to put our health completely in his hands with out a dose of skepticism...at least in the beginning. A couple of the GI doctors I've seen are probably pretty good at doing colonoscopies, and writing prescriptions for PPIs, but know next to nothing about GERD (even though they claim to).
What I'm getting at is educating ourselves to help find the best treatment for ourselves in the shortest possible time. I know it's frustrating to find cause-and-effect, because each treatment/therapy very rarely proves to us its worth in a quick manner. And, scheduling tests, doctor appointments, etc., delays things further...each time seems like it adds another 30 days to *maybe* move the checker piece forward one square.
Pepsin, in and of itself, most likely isn't the cause of reflux. If you've suppressed acid with antacids, H2s, or PPIs, then pepsin is the probable component of reflux continuing to cause damage. What needs to be done, individually, is evaluate what your symptoms are, and where they stem from.
By way of example, I have very few trigger foods, and have zero stomach issues. Diet is not the way to resolve my symptoms. I have a weak LES and UES, or at least they relax at inopportune times, and this is behind my reflux. This condition is not true for all.
It's even possible, in my case, that the individual episodes of reflux have been reduced as a result of my TIF such that I'm not receiving a significant amount of damage from acid, specifically, but more from pepsin. (The last two pH studies I had done showed that my % exposure <pH 4.0 is 2.9% -- almost as low as is theoretically possible with a Nissen.) Acid can be neutralized or washed away much more easily than pepsin, which apparently will bind to exposed cells and continue to cause damage whenever pH falls. But, I can't just stop the pepsin, if it's a component of the reflux that I'm experiencing. Gaviscon will block it temporarily with the foam barrier, but unless I keep everything in the stomach where it belongs, 100% of the time, I'm still going to experience symptoms.
I hope all this made sense. Just my two cents...
-Bruce