In the past you could basically duplicate a "Google only" campaign in a new campaign with search network enabled, and just make all the bids 5 cents less. 99% of the time Google would show the ad from the "Google only" campaign in Google search results, because it had a higher max CPC. But that doesn't seem to be the case any more.
All else being equal you'll normally see higher CTRs on the search network (because your ads are more prominently displayed, your ads appear right at the top of MFA type pseudo search engines, etc.)
And this totally screws everything up because this results in your search network ads having a higher avg CPM (even though the max CPCs are lower), which is what Google seems to rely on now in determining which ad to show (the ad from your Google only campaign or your search network enabled campaign) ... even on Google's own site.
So what's always worked in the past no longer seems to be working for us. We track campaigns using different destination URLs, and the majority of traffic going through our "Google only" tracking system is actually coming from the search network campaign.
So what is the latest and greatest method of separately tracking and keeping separate bids on google vs. search network traffic?