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Hi John, Are you still seeing the 'not mobile friendly' warning in the SERPs? I checked just now and wasn't able to replicate.

You're welcome. The canonical tag is used to prevent duplicate content concerns. Your traffic reporting is still going to register traffic at the sub-domain page visit.

You really should be using Google's parameter tool if you do NOT want those pages crawled. If they are crawled, and you use the canonical tag in order to tell Google to pass any "juice" to the page you're setting the canonical tag to, then you won't lose any traffic. Both of those URLs (the one with the parameters and one without) essentially will be crawled, but won't be indexed.