When DH and I dined at Shula's we did dress up a little. Definately better than park attire. I wore a pair of white capris and a silkey black blouse with some costume jewelry. DH wore slacks and a nice collared polo shirt. We took the time to dress up a little because we did not want to feel intimidated by others that were dressed better. Also we did not know how strict the restaurant was with the business casual rule.
There were a lot of business people in the hotel dressed very nice. However, our fellow diners were mostly dressed the same as us.
Please go and enjoy. The food will make you forget all about what anyone is wearing.