Started linkbuilding again on 3 year untouched site: rankings drop

Hello guys,

This thing is driving me crazy, so I thought I would ask you if anybody has some similar experince, or solution for the problem.

I have two 3 year old domains, they hit 1st page and some 1st places even in google two years ago, but I havent't done anything to them ever since, so the rankings dropped to 2nd-3rd pages.

I though I would reopen the projects, So I cleared up a bunch of HTML validation errors(I was quite newbie at that time), and started publishing, so that getting new links would seem more natural. I am building a silo for my original terms, so I am adding some content depth for the main topics. It looks like:
domain / original-term -> this had the rankings a couple years ago
domain / original-term / new-article1 -> freshly added
domain / original-term / new-article2 -> freshly added
etc..

I am giving some links to the new articles as well, but started linking again the original-term url, as main focus for my backlins, as those are my money terms.

Strange thing is that for both two sites I have reopened and started linkbuilding, rankings slightly drop. Not much just 5-10-15 places but more drops than gains.

I am extremely cautious with baclink anchors I have not used the same exact anchor 2 times, nor exact anchors for my key terms. I am backlinking with 100% unique 100% relevant and 100% human-readable 500-2000 character articles.

So for me everything seems like I am doing things as they should be done, and I am expecting to see slight gains instead of slight drops, yet the opposite happens.

Anybody had same experience?

First of all, the 500 to 2000 character article thing is a myth. You don't need lengthy articles to get top ranking.

For the fact that you haven't done anything in the past 2 years should tell you that your competitors are gradually taking over your position for building good links, that what it means.

And for the past 2 yrs a lot of things has changed in the SEO industry, i don't know exactly what you are doing but it may not be worthwhile anymore.

Well, yes you are correct with all things said. Frankly I have missed a couple things of the last 2 years and trying to catch up now, yet still: If I start building links from relevant articles, and adding relevant content to my own site, I would expect higher ranings, worst case rankings not moving anywhere but not dropping. Provided of course there is no eyword cannibalization, but I am heavily trying to avoid that.

Is there any way I could go wrong with this method? Maybe you can point me out something that I am missing here?

I say keep doing what you're doing. Google do have a patent out that tests how you respond to gains/losses so I say keep at it. Too early to tell IMHO.

It's normal for sites to drop slightly once you begin building links. Sometimes they drop out of the index completely (i.e. you can only see them by doing a site:domain.com search). Just keep building links but do it slowly.

Just keep link building but do it slowly slowly drip feed.