How to Validate an Idea

Here's the scenario: I have a new client who is working on "tightening up" their business idea. At this time, they need validation from people related to their industry. So far, they haven't been unable to connect to the right people for validation, and they've reached a stage where they think they can't go ahead with the idea. It's like a dead-end - wanting to launch an idea but can't validate it and yet don't want to proceed without validating it. Advice?

My proposal to them:
1) Organize a focus group. For each of the criteria described in the paper, ask the following questions : a) do you personaly consider this criteria important b) do you think our idea fulfils this criteria c) do you think our idea fulfils more this criteria than some other competiting ideas that you're aware of.
Marks would go as follows : strongly disagree = 0.25 / partially disagree 0.5 / half agree & half disagree = 1 / partially agree = 2 / strongly agree = 4

2) For each respondent multiply all the answers to get a global mark. Calculate the average global mark on all respondents and the root mean square. The average will tell you if the idea can work : the higher above one, the best chances. The root mean square will show you if it will work on all the targeted population or if you will only reach a sub segment of it.

3) By finding the commonalities between those who'll adopt the idea, you may be well inspired to take note of the demographic details (age, gender and all kind of details that you may find relevant) that will help in refining the idea.

4) Share the idea with members of an industry professional association and garner their feedback. Identify who is to benefit from this idea. Then, identify who among this segment will be open to play a part in validating it.

Throughout this process, it is important to let go of any selfish interest and agree to part with a little ownership or credit to the validating party as well. Keep the emphasis on the benefit that this idea will bring to the validating party as well.

MOST IMPORTANTLY: If you are unable to identify people who might benefit from the idea, then maybe you reall don't have an idea at all.