According to Yamaha:
"...By applying Partial Constant Angular Velocity (P-CAV) in combination with Yamaha's exclusive SafeBurn buffer management technology, Yamaha LightSpeed2 recorders eliminate linking errors common to high-speed data recording on CDs. As a result, Yamaha LightSpeed2 recorders are virtually the only choice for flawless audio recording and duplication on CDs. In fact, Yamaha remains the only CD-R/RW manufacturer in the industry not to give up recording reliability and quality in order to achieve theoretically higher recording speeds!
In contrast, Yamaha's efficient use of P-CAV technology allows writing to begin at 12X and increase at a smooth but rapid rate until it achieves 20X, 30 minutes into the recording process, without any speed zones or dramatic speed shifts, thereby eliminating the need for mandatory links to connect each zone. In fact, steady disc rotation has much to do with Yamaha's successful use of P-CAV writing technology where disc rotation remains steady at about 5500 rpm and decreases evenly as the outer portion of the disc is being written.
Other manufacturers using the Zone-CLV method to achieve fast writing speeds apply dramatically increased disc rotation speeds, causing the drive not only to spin much faster when it starts up, but also jump to even higher rotation speeds at each 4X increase. At each jump point, recording has to stop for a very short time. Each time recording stops and restarts, an intentional "error" link is created. During each link, the Zone-CLV method causes disc rotation speeds to suddenly jump by 20 percent every time there is a 4X increase (link) in recording speed..."
However most manufacturers that use Zone-CLV will tell you the oposite. How can we be sure about who is wrong and who is right? You will found out very soon