I represent Panda Express and my broker, Pete Podesta of UCR and myself have been looking for 2 years in DTD.
If you have ever been to Montreal, they have winter consistently and the underground shopping is a way of life, as is Minneapolis with glass walkover to compensate for the cold.
The underground system here is definitely a hindrance to grow. An asset is the inexpensive parking, however the streets lack excitement of foot traffic. Closing the underground would certainly help push the consumer to the streets and could possibly help the growth of food or retail stores.