For another, it is difficult to formulate a true double-blind randomized trial for acupuncture, so it's not like any study on it is free from questioning to begin with. You can't compare it to "no treatment", because then you have a group that knows it hasn't been treated. They usually do "sham" acupuncture to be the "placebo"/baseline, but you're still DOING something so it's not a true placebo. We don't know the exact mechanisms, so we can't say for sure that "sham" acupuncture does nothing. And the body is just full of points so who's to say you're not inadvertently "Treating" (if you're truly just hitting random points in the body). It's like..oh...you're trying to formulate a drug to quickly alleviate hypoglycemia, but you still use a "sugar pill" as your placebo. Obviously that'd be a poor decision, but think of that operating under the assumption that you don't know the sugar pill will help the hypoglycemia. It's not a great analogy--I apologize--but I think you can see my point?

Additionally, there are a number of clinical trials in animals (I've done the most reading on trials in horses) that show efficacy of various forms of acupuncture OVER sham acupuncture. The result is usually the most significant when electroacupunture is used. There certainly can be bias at many points in the trial process, but it's pretty much impossible to get what most people think of as a 'placebo effect" from a horse. And it'd be unlikely to be a positive bias on the part of the horse (I have yet to meet a horse that likes being manhandled by scientists or poked at with needles).

I'm NOT trying to say I 100% wholeheartedly think acupuncture is totally valid. Obviously we have a lot of questions about it, and how it can be used. But to write it off entirely based on flawed studies flies in the face of CENTURIES of clinical and anecdotal data in numerous countries, as well as studies performed with other species (and before you go writing that off, remember that most studies for drugs/etc... start with animal studies). I know people who have had very good responses to acupuncture and modalities of treatment that are based on similar principles. I know many horses that have responded very well to acupuncture. Acupuncture probably doesn't work they way we think it does and it probably doesn't always work (nothing does). But to write it off completely is depriving yourself and others of a potentially useful treatment modality.