Progress report: I increased the speed to 66ipm (CL 0.0027), and increased the DOC to 0.02", keeping the same RPM. Also used a brand new 2 flute 1/4" bit. Edges are much cleaner, there is no burning of the MDF spoilboard, and the chips look good. The third try was good, and is shown.
Could probably increase to 72 IPM (CL 0.003) and the DOC to 0.04".