Well, nobody said that he is doing something wrong; it just don't make sense to me that he is spending money and time to produce something to just put out a preview and say "hahaha! you don't get it"...it may work maybe with schoolmates when you show your last gadget, but for a company that lives selling videos I do not get the point of doing this....whoever is pirating the clips is not having anything negative out of it; while Darth and the guys that wanna buy his stuff are getting the bad side of the deal IMHO.
Maybe is to keep the interest high while no new clips are released? Sorry but i do not have a degree in marketing or am a guru of capital ventures and such...i sell software not tickling clips
And of course I am not saying that the customer will leave Darth; just that personally as customer, I have a budget, and between waiting for new clips and getting clips on another store I go for buying on another store....nobody said that I will never get Darth's stuff anymore; that would be illogical and totally childish I think.
Piracy is something that is part of our life; and as you said is not the youtube video that hurts the market; especially when you have hundreds of clips (on youtube the most of the tickling videos pirated are from TA and CZ Tickling; 2 companies that has hundreds of videos and for them one or 2 videos out for free is not that much of a loss); but when you sell an honest amount (no clue how much it is, depends from everyone's expectations), it hurts to get something out that gives you a loss.
As example my software goes between 9.99 and 19.99; and even one single copy bring me a loss, while if half china pirate windows, microsoft can continue to live and make profit without even care.
There is no way to stop piracy, not even if you add protections or secret ID to each clip, so you know where the spread started (someone must have purchased it on C4s; if you know who got it, you can find out to whom he/she gave the clip and catch the whole chain); when i was voicing my concerns on a security forum, about what is the point for small software houses to make software due the piracy; I've got unanimous answers saying "live with it or just give up"; and now I realize that no matter how much effort you put, someone will crack your stuff no matter what, sooner or later; so I just add a minimal protection to discourage the occasional kid that wanna pirate the software...and take the piracy as free commercial advertise for my products....the last thing that I would do is to just show new products and say "sorry but you cannot buy them"
but that's just me of course...anyone is free to do and act in the way that fits best.