The short answer is most definitely, as you can see significant spikes in traffic that way. However, as with most things in life, it’s about doing it the right way to get the best results.
Which posts deserve attention?
In most well-established blogs, there’s always a hardcore of older posts that still bring in lots of views and traffic, even if they haven’t been updated for months. These posts, all totalled together, can bring around 60-70% of the traffic into your blog and you might think that it’s not worth fixing them if they’re not broken.
You’d be wrong, however, because adding new content can mean they see an uptick of around 15-20% in traffic, which is a big deal if they’re already bringing in the bulk of your views.
Then there’s other worthy candidates
Look at the posts which get the most organic traffic (that is, through keyword searches rather than links). Depending on how long your blog’s been running, you could have 25 or 50 top-running candidates that are pulling in the punters. Now, you can’t treat every single one to some TLC all at once, so pick out the five most productive posts from this list.
Weigh up the updating time compared to the benefits
Let’s say you’ll take 30 minutes to update a post that brings in 1,000 unique visitors a month and that update earns you an extra 150 visitors. How much would you have to pay in PPC to get 150 extra views each month? It’s almost certainly a lot more than the cost of spending half an hour giving your faithful servants a revamp!
Don’t neglect the poor performers, though
Some poor performers are so because they’re seasonal, or they’re related to some news that’s fallen off everyone’s radar. If there’s an update to the old news, spend five minutes dropping it into the post; if it’s a seasonal how-to post, refresh it by bringing in new products or techniques. Don’t spend so much time on these posts, but just give them a bit of a primping so that you benefit from a brief spike, then leave them until the next year or the next new opportunity.