Hi Abel,
Yeah I've checked the TODO list a couple of days ago, and the idea of working on the doc passed through my mind while struggling on some fishy details I couldn't master, or things that would have been much more understandable if they had been embellished with the extra infos I got on the forum (just like this one).
But how can I explain it ? I'll just be able to say "well mates, just maximize your light depth

". We got to find a link between this tip, and the real knowledge behind it, which the reader has to learn. I guess there is a lot of communication between Dev and Doc team ?
As a matter of fact, there are things in the TODO list that cross my personal tests list...so I think I'll tell you soon about things I'm aiming for. I also have some suggestions passing through my mind. So we'll see that by PM as you proposed.
I won't give up on a (little at least) starting up guide. And if I feel I finally got the knowledge I'll definitely submit one. You need to boost your community by collecting some fresh innocent people, that's how you will (at long term) settle the problem of the lac of materials in the database for example.
About the way it should be made, I don't know, I think it can be realized alone with some über-welcome tutorial files....then we could in the feature list say "refer to tutorial scene X to tweak that feature !" That would be so much more communicative and that seems similar to your proposal of setting examples to illustrate, but it's interactive and ready to use :p
For the tutorials, I'm following some right now and I think the current line-up is not efficient yet. There are (in my opinion) About hierarchy, about gaps, about up to date or not etc...for example, that wonderful soap material, with those cool lights etc, I'm dying to achieve it, but I think people need a bunch of preliminary tutorials that don't exist yet to be able to follow.
Whatever, for now I must insist on that fact : I'm beginning with Blender 2.5 (and I've never been a 2.4x killer) and about Lux, you must have guessed I'm a beginner.