Apparently it's not easy to poison a website's link power. . . so far

Interesting test. What was its existing link profile like?

Interesting experiment! Keep us posted.

Are there good quality links pointing at those spammy domains? Maybe those links to your old site aren't being found.

Ditto. Interesting experiment....

Are there good quality links pointing at those spammy domains? Maybe those links to your old site aren't being found.

To take this thought one step further, are you monitoring server logs on your spammy domains and on "small old site" to see if Googlebot has crawled them.

I can't put my finger on where I saw it, but I believe that someone at Google said recently that it might take 90 days for non-busy pages to get crawled, which can slow updates of some sites. Conceivably, depending on where various sites are in their spidering cycles, this might push you well beyond 10 weeks.

Interesting. I have always wondered how long it takes Google to react to any major positive or negative ranking factors (linking, major layout changes, etc...). I realize this depends on the size and popularity of the site (among other things)...

Once you successfully tanking the site with spammy links you should submit a disavow file to see how long it takes to return your old rankings.

it takes much longer to see the negative (or positive) impact.

The old site still has a small set of quality backlinks that had been decaying for years. Googlebot has visited all sites.

Tentatively confirm negative seo is in retreat.

10 weeks isnt long enough I heard sometimes the algorithm doeskin update for penguin for at least several months

Go to blackhat world and invest in some of their fine private blog links and toss in some fiverr blog links. If you are going to test, throw some fuel on the fire.

The most logical answer to this situation will be that there are definitely many others who thought of the same /similar methods like you. But, not everyone is simply attacking their oldest sites. Google naturally will be using some pattern recognition automation system to differentiate between an intentional test or a malicious attack, most likely without actions till your site's rankings supposed the highest ranking "dead site".

There isn't "secret formulas" from Google, they just have the search pattern and behavioral traits of approximately most of the humans in this planet. Naturally, they can derive many advanced technology. The problem with Google, is they have embarked upon a path that focus solely on monetizing their current resources while competitors while keen in profits, also thinks of how their services can be more productive for the society. Googling any popular search terms, and getting #*$!ty obviously affiliated results are a waste of time.