Planet13 - 2:59 pm on Jul 3, 2013 (gmt 0)
@ Robert Charlton:
It might help to think about such links, particularly contextual links, from the user's point of view. If the user is reading an informational page and, say, your first use of the "blue widgets" phrase on this page is a contextual link, I think the reader might naturally expect that clicking it would lead to more information about blue widgets... If I were so misled, I might leave the site... or certainly back out of the link.
Yes, I can certainly understand that.
But the metrics don't really confirm (nor deny) either way. It has one of the lowest bounce rates on my site. And while the time on page is lower than the site average, I feel that is partly because it is a category level page that links out to all the products in that category, so people who come to that page often quickly click on a link to the a product detail page.
The blue_widgets.html page does have one of the higher ecommerce conversion ratings, and since the vast majority of the traffic to that page is from people clicking links in other pages (since that page is not in google serps at all) at least some of the visitors who are clicking links in the pages are buying things.
However, I do think your idea of setting up clearly distinguished buy buttons is better.