Forum Moderators: not2easy
You could test it pretty easily. I recently stuck a piece of frame-breaking code in every page on my site. In some cases, that was the first time the pages had been modified in 4 or 5 years! And all of a sudden, I had all-fresh pages.
Had no impact on referrals from Google that I could see. Maybe it did with other SEs, but I don't get enough traffic from them for anything less than a doubling of traffic to be obvious.
On the other hand, I got a definite jump in traffic from a site redesign. The main section of the site had a huge list of pages linked to from it, and it was hard to find stuff by browsing. I created sub-category pages, listed them on the section page, and no more than 20 articles each on the sub-categories. Traffic up overall about 30% almost immediately, and it's stayed up ever since.
Add new content. If you think you've covered the subject, you haven't. Invite questions from visitors and post a weekly question with your thoughtful answer, then archive the pages. One may even turn into a new article. Some new content weekly or even monthly will at least get the search engines visiting regularly.