Yup, this is actually how we used our EMH at MK last trip. It was nuts going up to the castle/Dumbo so I made the executive decision to duck in MSB and get breakfast. We were not far back in line, got a great table, great breakfast, and made it to Dumbo before regular park opening and after the initial chaos. It was nice. Got some great photopass pictures and enjoyed our leisurely stroll up Main Street.