Would be the network site map page considered link spam

[romanbond]

In the course of the last 18 months my sites have lost from 50 to 70 percent of traffic. Never have used any tricks, just simple white-hat SEO. Anyway, I am now trying to fix things that hadn't been a problem before all those Google updates, but apparently now are. Would appreciate any help..

I used to have a network site map page on everyone of my sites (about 30 sites). It basically would be a page called 'our network' and it'll show a list of links to all of my other sites. These pages were indexed,  had decent PR and didn't seem to cause any problem. Here's an example of one of them:
http://www.psoriasisguide.ca/psoriasis_scg.html

In the light of Panda and Penguin and all these 'bad links' I decided to get rid of most of them. My traffic didn't recover at all, it actually went further down. Not sure if there is any connection to what I'd done.

So, the question is: In your opinion/experience, do you think such network sitemap pages could be causing penalties for link spam?

[DennisSeymour]

We've actually seen this kind of behaviour with some of the sites from new clients.

They interlinked all their websites, usually with the same templated design.

If you didnt get any warning in webmaster tools, this is probably a purely algorithmic issue which is a whole lot harder to get out of.

I would look at the other things, technical seo, onpage, content being updated, those sorts of usual seo stuff. You competition might be different now in the SERPS as the keywords you were targeting are now showing different results.