I'm from up North and a sweatshirt to me would be a jumper. The guy's desciption is misleading, but I'd take it to mean they were t-shirts as thats the last descriptive word.
I wouldn't leave negative feedback unless he's arsey about a refund. If your keeping the tshirts then leave positive feedback as there's nothing wrong with them, just not what you expected. You can mark him down for his description as they now make you give him a rating for description/packaging etc.
If you want a refund and they start being awkward, then leave negative feedback.
