Well, the word "proven
diet" in the glider community means very different than "proven" in a science sense, and it can be misleading.
In science, for something to be "proven," you have to do multiple studies with controlled variables, gather a great deal of evidence, and after multiple trials and peer review, there is reasonable assurance that something is "proven" or accepted as true (unless additional evidence comes up indicating otherwise).
Here (aka the glider community at large), "proven" seems to mean that many people have used the
diet for a long period of time with reasonably high success.
What we are marketing as "proven"
diets are not BAD
diets. They probably are a better alternative than everyone trying to make their own
diets, because frankly, many of us, including myself, are just not educated enough in nutrition to assemble a healthy
diet, and using a more "standard"
diet like BML or Suncoast that has a reasonably large amount of evidence indicating that most gliders do well on it is a safer option.
However, we must remember that this isn't necessarily the BEST or the be all end all. Part of the problem is that even the scientific community and the
vet community in general (probably moreso in the US than Australia) just don't know enough about gliders' exact nutritional needs to mandate what exactly is best.
In fact, the one dietary study that came out recently on gliders that I DO know of found that the gliders on BML didn't necessarily do better than the gliders on the other
diets; in fact, they raised pretty grave concerns about possibly too MUCH vitamins in the BML. This is not to say BML is bad, and there were many potential problems with the study (small sample size, cannot determine long-term effects of
diet, etc); it's just to say that we have a lot left to learn about what
diets are best for our gliders.
All of this in consideration, going with a "proven"
diet is probably safer for most of us, since we are not nutritional experts. However, I think that having open discussions about
diet and sharing findings is important. We shouldn't poo-poo people with alternative
diets (unless they're only feeding SPAM or something) because their
diets may be equally viable to the "proven" ones.
The only way that we can improve
diets and welfare for our gliders is to continue to learn and share our findings. I'm sure
diets out now are much better than
diets were for most gliders 10 years ago, and hopefully in 10 more years, we will have made considerably more progress in doing what's best for the gliders.
Sorry, that was long.