tedster - 6:07 pm on Dec 28, 2007 (gmt 0)

One thought occurs to me - we can check our own server logs for "one-hit wonder" visits from Google Search to the affected page. Narrow it down to only those visits thast use the problematic keyphrase. We may not have Google's click-back data, but we can check our own server logs to see if the page is not performing as we expect it to.

If there does seem to be a performance problem creating one-page visits, then dig deeper. Look for page load problems and errors, check whether the search phrase is prominent and above the fold for all common browsers, and so on.

Also Google Webmaster Tools shows you the top 20 search terms where your url got impressions as well as the top 20 click-throughs. Any serious discrepancy between the displayed and clicked-on numbers might indicate a need to change the meta description - or possibly the Title element, but be careful here because the Title is part of the relevance scoring.

That left hand column in GWT's Statistics > Top Search Queries gives you data that you have no other way to access - it's one of GWT's best free gifts to a site owner:

Top search queries The top 20 queries in which your site appeared, and the percentage of the top20 queries represented by each search.