Shenmue Dojo

I do have fond memories of old PSX demos changing my life, the Jampacks, the Green and Purple "PlayStation Picks" discs, not to mention the FFVII demo and things like that. I think a demo can have a lasting effect on its own. It's not usually just a slice of the game too, often it's specifically crafted to have a definitive end for the demo player. That being said, will I play it? I'm not sure, because in this case, we know the game is coming, so I'm not sure there is really a punch there.

I think if Yu plans to use this demo to alpha/beta-test the game in order to receive some feedback for further refinement and polishing: it could contribute to their development positively. I don't own a powerful PC but i already made arrangements with friends to lend me their high-end gaming laptops for a bit so I can play this once it releases.

I don't think he needs to go out of his way by making the content unique of representative of the final game, but if he wants it like What's Shenmue: I imagine he will to some extent as first impressions are important (demo or otherwise, especially is the release is some time away).

As long as he can take steps to ensure no spoilery stuff can be mined out of it (as you've already mentioned) and can use it to improve the final build i think it'll be worth his time. Otherwise if he decided against it I wouldn't blame him (although I imagine he'll follow through regardless since he wouldn't want to upset those at the $100 tier...)

I don't even want a demo, unless it was more like a "What's Shenmue" thing. Last thing I want after a lifetime of waiting is to spoil any of Shenmue 3 by playing the non final product. That day will be a sacred day for me and the final product is close enough.

If I remember correctly, Suzuki said the demo would be something similar as What's Shenmue.