This has been going on for a long time and I don't believe it has anything to do with clicks being invalid or 'tricksterish'. There was some wording in the Adwords blurb some while ago that got changed, but it explained their way of thinking.
Advertisers don't simply want people to arrive on their page, they want some kind of a result after that happens. This takes a little time. If the user clicks through and then goes straight back because it's not what he wants, then that click gets taken back because there was no result. Google knows the user didn't do anything because of the time taken.
I don't think this is fair on the publisher, but it is Google protecting the Adwords users because they pay the money.
For a long time if I log in and see two quick clicks in succession, I check to see if they were on the same URL and from the same country. If they were it probably means it was the same user. The user clicked on an ad, returned, and clicked on another ad. If this happens, then 99% of the time one or both clicks will have been removed when I check next time.
Whatever gripes publishers may have, Google aren't at all bothered. Their loyalty is to paying customers and shareholders and their shares are now at record highs.