This morning I rode through that intersection as usual, and then I looped back to see it from the perspective of the driver who almost hit me. Stopped at the stop sign on Charlton Street, I looked left and right to find how well I could see traffic along Payne Street. The view southwest toward Spring Street and Lexington Road was clear. To the east, I could see clearly for at least 200 feet. As I approached the intersection yesterday at 24 mph (or 35 feet per second), the driver at the stop sign should have had roughly 200/35 or about 6 seconds to notice me before I rode into her path. Six seconds sounds like a short time, but it's much longer than the 1 or 2 seconds needed to see and respond to an oncoming vehicle.
In other words, a careful driver at that stop sign at Charlton Street would have easily avoided any conflict with an oncoming bicyclist on Payne Street. The intersection can certainly be reconfigured to improve safety, but my first reaction was probably correct: the driver who nearly hit me had no excuse for causing this close call.