SAN DIEGO (TheStreet) -- Confession: I had never heard of Voxeljet (VJET) - Get voxeljet AG Sponsored ADR Report, the 3-D printing company, until yesterday. That's when the stock collapsed after Citron Research wrote a scathing report.
Voxeljet's crash landing pulled down the other 3-D printing companies in classic knee-jerk fashion.
Could they all bounce back? Today all but Voxeljet did.
In the end, as even Green Mountain (GMCR) shows today, in this market it's more about the story than the substance.
Make no mistake about it: 3-D printing is real and will likely revolutionize manufacturing as we know it today. Who knows, maybe soon the 3-D printing and Green Mountain stories will morph to Green Mountain using 3-D printers to create its K-Cups. Then there's Tesla (TSLA) - Get Tesla Inc Report. No talk of 3-D created Tesla cars, yet, but no dispute that the Tesla is a really cool car that has already turned the auto world on its head.
But any of these companies really worth what they're trading at? Of course not. Certainly not now.
Owning them is a gamble. Not owning them is gamble. Shorting them is, well, as Green Mountain showed yet again today -- perilous.
As Travis Cocke of the Voss Value Fund writes in a letter to his shareholders:
"This mistake in shorting Tesla and a few other momentum-driven names has not been in misdiagnosing them as a tremendous bubble, but in inaccurately anticipating the magnitude and especially duration of irrationality inflating them. The problem for a prudent investor or bears is that events in the distant future are as hard to disprove as they are to prove, so logical arguments dissuade very few believers from buying at extreme levels."
"Everyone wants to talk about their recent successful speculative episodes. People inevitably get giddy to tell you about how they bought Solar City calls before a pop or day-traded a triple-leveraged ETF."
"I vaguely remember a striking quote from the showman David Blaine that I'll paraphrase. Although I cannot quite remember the context, that is not what's most important: 'As a kid I liked to hold my most prized possession out the window of my parent's car as we sped down the highway, seeing just how lightly I could hold onto it without losing it forever."
"Like Mr. Blaine, some participants in the market are aware that they are tap-dancing on thin ice and perhaps actually enjoy the thrill and sense of danger of losing their personal savings or previous investment gains (easy come, easy go), while others are altogether oblivious to the risks they are taking and to quote GG who likes to quote GG (George Giannukos/Gordon Gekko) they 'don't know the difference between livestock and preferred stock'."
"These noise traders are vehemently defending or promoting stocks with impassioned garble that 90% of the time neglects what is most central to any investment decision: valuation. More and more we hear the meme that valuation doesn't matter..."
And it doesn't, until it does. Just ask investors in Voxeljet.
--Written by Herb Greenberg.
Herb Greenberg, editor of Herb Greenberg's Reality Check, is a contributor to CNBC. He does not own shares, short or trade shares in an individual corporate security.