If we are going with the stated reasoning, I'd probably drop the "foreign" part. Midwest/Californian/New England/Texan are all mutually comprehensible but ther

If we are going with the stated reasoning, I'd probably drop the "foreign" part. Midwest/Californian/New England/Texan are all mutually comprehensible but there are some deep-south accents (I am thinking particularly of rural South Carolina) that can cause the exact same sort of communication friction. Also, I doubt a strong English accent would cause much trouble, despite being both strong and foreign.