No solid conclusion reached!
Zone-CLV has switch-points, where there will be a link, and a loss of speed while recording, but has only a few speed-calivrations to worry about.
CAV mode has a constantly varying burn speed, so relies more heavily on "running OPC" to adjust laser power - the timings being controlled by the pregroove clocking.
CLV is the oldest method - the data rate is constant, and the physical RPM decreases - most drives will use that at speeds of 16x or lower.
P-CAV (Partial CAV) - is when the drive starts off in CAV mode (at the maximum possible RPM), and then (steplessly) moves to CLV mode when the maximum possible data rate is reached - to keep it in full CAV, would mean starting from a slower speed, or being able to finish at a higher one.
