I realise trusting my memory is dangerous, but I seem to remember a comment from a professional who used to post on this site. It was at least 18 months ago.
The comment was that an individual who did not include their UK employers pension contributions on 1040, and did not include an 8833 with their return was deemed to have elected the use of the Treaty exemption. This was not an official statement by the IRS and I would defy anyone to find such language written definitively anywhere. File under hearsay, but it came from someone I would trust.
DISCLAIMER:sent from my watermelon using oranges and apples. (
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