Question for +John Mueller and/or +Pierre Far regarding hreflang alt.

In the following blog post ( the author comments:

Actually when rel canonical and hreflang are both present, URLs w/ rel canonical ARE pulled from the index. hreflang simply allows the display URL to fire at search time. The title and snippet text are taken from the rel canonical target.

You need to be very careful here and understand the functions of these annotations, both separately and in tandem. I’ve spoken in detail about this w/ Google’s team. This is how it works and why it’s so important to watch rel canonical carefully, because it can and will yank an international site from the correct regional index. No one wants their US title and snippet text showing for their UK site. The URL is only 1 element of a successful search presentation, and in the case of hreflang, the URL is simply a display element fired at search time.
I'd ove to get confirmation that this is the behaviour that will occur (as the author also states this hasn't been tested)? If rel="canonical" is used in conjunction with hreflang alt will the "dupe" page be removed from index, and is the hreflang attribute only going to affect the display URL?
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