In theory it sounds nice but in practice people may be hesitant to make their idea public to X number of strangers whom they've never met. You'd also need to find a wide range of domain experts to participate. What is their motivation?
You raise a great point and honestly my two hypothesis are
1) People would realize that its very valuable to get the opinions of strangers before "wasting" time creating something they think they might want. One could argue that talk is cheap but I'm sure this guidance can lead to very valuable results maybe rethinking the idea or whatever the case.
2) You don't need domain experts in the beginning per se, just a bunch of minds who can quickly determine if they would use or not use a service. The motivation behind domain experts joining in the future might be just to help and give back to the entrepreneurial community (I admit this last point is kinda corny lol)
My guess is that you'd find a connection that works your particular area to validate the problem. If it's a first level connection that's great, easier to ask :). Otherwise, find a second level connection and get introduced to them. Say that you'd like to discuss some of the problems that they may experience [as a teacher, entrepreneur, etc]. People love to talk about their problems to someone who will listen.
Yes, exactly caw - thanks. I view LinkedIn as one huge convention center, and the worst that can happen is people decline you connection request. If you present an honest and positive tone, people will be more receptive. Then it is possible to PM select connections to review your idea or beta, etc.
