and continuing with the SEOs who aren't stupid but were making money by keeping quiet.
Kackle you have weighed in again with the conspiracy theory, one which I might say, does not exist IMO.
IF there was a conspiracy of silence, then this very topic would have been deleted at the outset and not debated for the world to see.
I tell my clients 3-6 months, I do not arrange thousands of low level links, I do not buy links, I simply do the same as I have always done, I put the key phrase into my 'link search engine' and it comes up with the sites to submit to in order of importance. I then get on with submitting them. Not at a rate of thousands per month, but the normal tortoise style link building. Day by day, they climb the rankings until after a while a trickle of business comes in from the organic listings. day by day, more and more business comes in, until eventually we get what we were aiming for, and can drop our paid listings completely. the job is done. Just tweaks and maintenance/development from then on in.
I understand why so many people are up in arms, I openly admit that IMO the sandbox is real, (But I have done this before so nothing new there). The thing is that the bulk of people at HR do not go down the 'fast 'ink' route, and, as such the problem does not happen to them very often. It is not a case of conspiracy, or cover up, it is a case of apathy caused by a lack of vested interest.
If you want to run a test, how about this then. Make two sites about similar subject matter. Place them on different c class ip's, arrange bulk links to each page from the same pages and no where else, identical links for both!
Now optimise one traditionally as well as you can without going overboard. The second leave as rough as a badgers backside poor title tags, etc very little repetition of the keyword in copy. Now wait to see if one or other or both gets sandboxed. If none then add more bulk links until it trips the sand box. If both then fair to say that it is purely link volume that trips it, if only the optimised one, then you will know that the sandbox is linked not only to link volume, but to other aspects of the algo, and is applied 'after' on page factors have been evaluated.
I will not take part in the test, as I don't have the time, and really have nothing to gain from it, but that would certainly be the first test I would run.