I think the answers to my question of whether tweaks work or are fraud both are yes. IMHO, and I think in everyone's humble opinions some work and others don't. Again in IMHO, one cannot judge a tweak by ones failure to understand how it works or even whether are not many others have found it beneficial. All that really matters is whether one finds it beneficial in ones own system. Given my personal experience, even within ones own system a tweak that works at one time may not at a later time, when your awareness brings to the fore its side effects or when something changes in your system.
As to whether some tweaks are frauds, again I would say the answer is yes. But I think that there are less costly tweaks that are designed to be inexpensive that to some offer little or no benefit. I have personally experiences many tweaks, some of which have no benefit for me but which others find beneficial, including some who I greatly respect. Are they frauds? I think not, although I even hear losses in using them.
Why did I introduce this thread? Because I do not think it is a simple issue of fraud or not., or work or not. I also think personal understanding of the physical principles involve is not a worth criterion for what is fraud and what is not. Scientists have often made such judgments about new ideas only to find later that the new ideas are correct and existing theories need to be altered.
Too often discussions of new components, Memory Player, or power cords, or tweaks discussions end up in what Newbee prefers to describe as "pissing contests." This is true in science also, but at least there most offer alternative explanations of what is going on. Fortunately, in audio it is merely whether or not to buy a tweak or componet. If one likes it, I cannot understand why anyone would argue they should not buy it, whether or not the critics understand how it works or have even personally found it useless.