Some A1 members would like SEO's to (possibly) engage in a challenge by starting a website from scratch and implementing your own advice so we can see the progress.
SEO's in this place, myself being one of them, offer free advice and help to people with issues. Isn't that enough? If you want to know if I'm any good - say if you are going to hire me - then I'll provide references
When I give advice in here it's often not implemented. It's often not implemented because the people have sites that are inflexible (thanks to the shocking state of the web design profession). The free advice people get in here works, I see no reason to use even more of my spare time to prove I know what I'm doing or what I say is valid. As they say in Dragon's Den - I'm out, but I'll still be around to help those in need
Its not about proving oneself, its actually so people can see it to believe it - people find it hard to believe something they cannot touch, feel or see before they do it, either themselves or pay someone to do it.
For all that is said, if it could be shown and seen, I think it would motivate and spur people on, as all results do.