On Scottrade, I think all I can judge the size of the buys/sells on is from a bar chart on the page (unless someone else without L2 has a better way of seeing this stuff). From the volume sold today, the second half of the day didn't even register as a bar at any point, since I guess it was so much smaller than what was done earlier in the day. That's why I just assumed (I guess incorrectly) that it was a paint job.
This guy sounds like a real treat that you're talking about.