" . . . a trick of words . . ."
I think that exact phrase has been applied to Anselm's ontological argument for the existence of God. But I'm not sure that such a criticism is any more substantial than the thing it critiques.
There is, I think, a measure of the abstract in all existence. Some people call it spiritual, some metaphysical, some the Gospel, the Tao or simply the mystical. Science allows us to view, measure and verify the concrete, physical substance of nature. But if we remove all of that which is physical, what is left? We know that science offers us physical explanations for things like feelings, thoughts, emotions and such. But what are the things themselves? If I say I'm in love with my wife, some will cite hormonal reactions, some will measure my heart rate or blood pressure increase (or decrease) when I am near her. Some will insist that the emotional, erotic or asthetic reactions I feel are based on these physical responses to the stimulus of her presence. Others will argue that the feelings themselves produce the physical reactions. But none of these approaches will actually define the thing itself.
If there is a spiritual substance, how can we define it or measure it in a physical way? Whether we are discussing the existence of God, the power of magic, some paranormal force or the oneness of the universe we are discussing a reality that (if it exists at all) cannot be defined in real (physical) terms. The best we can do is use our physical senses and communications capabilities to express ideas. That's good enough to discuss, say, a tree because we all perceive trees consistently. (To remove an objection, what I see as a tree might look to me like what you see as a frog, but we will see all trees or frogs the same way individually.) But while for practical, physical reasons we all know what a tree is, I would argue that nobody ever sees a tree itself. We see the reflection of light off of a tree, not the tree itself. We feel the reaction of our nereves to contact with the bark of the tree - not the bark itself. We hear the vibration of our inner ear caused by the wind rustling the leaves - not the wind or the leaves themselves. But outside of a biology class, which seeks only the concrete, or a discussion like this, which seeks only the abstract, we don't give much thought to the existence of the tree when someone shouts "WATCH OUT FOR THAT TREE!" But the idea of a tree, a frog or a person - that which, removed from the physical, or the spiritual, simply exists - that cannot be defined as an absolute truth. Not yet, at least, not on this plane of existence.
I'm not trying to define BSB's concept (though it sure sounds like it, doesn't it?). I wouldn't know where to begin - since I make no claim to understand it in the first place. My point isn't whether we are real or a reflection (or memorex for that matter). I'm really actually sticking to my original point, about the term "trick of words." Words are pretty much all we have to discuss any concept higher than maybe "big, scary thing behind you!" Words are a trick in themselves. Every idea we have is expressed in words, which can have many meanings and denotations and connotations and nuances (oh that word!). If this were not so we wouldn't have thousands of Christian sects all reading the same Bible and coming up with wildly divergent doctrines or thousands of lawyers reading a short document written over two centuries ago and making a damn fine living arguing about what it all means. But words are completely inadequate to express the most profound ideas. That's why everyone relates to the phrase "Words fail me." They often do.
So if the only tool BSB has to try to express a deeply profound personal concept is words, he has no choice but to use an imperfect instrument to describe a perfect ideal. To convey even a portion of such an ideal with words requires all the tricks one can force out of them. I understand that feeling. I cannot begin to describe what I mean when I say "I love my wife" or "I know that my redeemer lives." Words fail me. If conveying those sorts of ideals must be done with words, than calling something a "trick of words" is not a disqualification of its meaning.
Anselm's argument fails when other "tricks of words" are applied to it. Yet it expresses something that, in spite of its own imperfection, is nevertheless perfect - and true.