* In order to think through this, Dan and I walked around the same block in Mountain View several hundred times

Don't. If your startup is trying to sell to small businesses, stop asking the business owners on Castro St. They already have more pitches than the VCs on Sand Hill road. They are bombarded with half-baked ideas on how to get more customers, make more money from existing customers, etc.

Long distance calls have been free for a while now: call some other state with no startup culture and pitch to those business owners. They'll be both more receptive and more representative of the overall business population.