Not real in any way, just a concept. If it gets the guys on the field, I think they'd adapt. We may be entering the age where every player and coach gets a transceiver.
Too restrictive in vision and airflow.
Make the lense area bigger and it might be alright for cold weather but I sure as hell wouldnt want to wear it in the warmer months.
Of course the lense would have to be dual pane so it wouldnt fog up.