I'm building a site in free Acquia cloud env with apache solr running, I need to count when a node (for one content type) is being full displayed, that’s already working fine, but every time I refresh results page (viewing only teasers), it triggers not once, twice in all nodes within the content type, so my node full displayed count is not correct, Rules only option is 'when node is being viewed' and not 'node being displayed', I have to mention that this count field is to set solr sort results with a custom module (already working), any suggestions please?
I struggled with a similar question ... The "clue" about what "Content is viewed" actually means, seems to be like so:
The event Content is viewed is what it is: the user has (already) started viewing the content.
The (system) event Drupal is initializing is what you should use instead (possible combined with other Events and/or Actions), if you want to trigger some Rules "Action(s)" BEFORE the user can start viewing (= looking at) the content.
For more details, and a working sample (in Rules 'export format'), refer to How to specify a Rules event like "Content is 'going to be' viewed"?
So in your case, it'd be interesting to find out what result you'd get by using (system) event Drupal is initializing instead ... definitely worth a try I think ...
Be aware: this applies to D7 ... and D6 is another story.