Very sad, and sobering news to receive while on the ride. Didn't ruin the event for everyone, although some were impacted. Many of us were held at Tolmie before the descent into Mansfield (the main road was closed pending investigation) until a route around the incident was proven. We were then released in groups with designated lead riders, did most of the descent on the road and then 3 to 4 kms on a gravel road around the incident, coming into Mansfield on a different road.
From what I heard: Cyclist was apparently experienced, but clipped the wheel in front and fell onto the road. Truck following was going relatively slowly, but couldn't avoid someone falling into their path.
Lots of good signage on the road warning motorists, reduced speed limits in most hazardous areas, route marshals at intersections and lots of police visibility - cars, motorcycles and 3 on bicycles. I felt more at risk from a relatively few people who either didn't know how to ride in a mass participation ride, or didn't care, than I did from motor vehicles. Still, most of the time it just wasn't an issue as the ride was strung out over kilometres.
Riding the Black Spur was a highlight - with the road closed. It rained from Alexander to Marysville, then stopped so the ride over the spur was dry. Couldn't leave Marysville before 10:30, then another stop point at the Black Spur Inn - couldn't leave until 11:30 after the road closure was in force. Sent off in groups so the rider density wasn't too high, with police motorcycles moving up and back to ensure good behaviour.