Google Analytics provides useful link navigation reports (Site Overlay, etc). However, if I have multiple links to the same destination URL on a single webpage, GA will not be able to differentiate the clicks to each one. One solution presented by Brian Clifton in "Advanced Web Metrics" is to add distinct parameters to the separate links:
I would like to implement this but am concerned about potential adverse effects this could have on the indexing of our site and SEO. Does anyone here have experience with this issue or have any insight?
Search engines tend to not like seeing the same page with many different URLs, so that's one problem.
Another is that, should a search engine actually index one of those URLs and display it in results, your analytics reports will count those visits as if they came through the home page side bar. It doesn't take long to destroy the integrity of your data.
Consider, instead, adding those tracking parameters via "onmousedown" actions. Spiders don't click mouse buttons so they won't pick up the extra parameter. You will then get correct data if you look at the stats for the different parameters. But you won't be able to view them in Site Overlay, of course.
Alternatively, use nofollow on those links to try to prevent spiders from using the links at all.