On the AD951x clock ICs, does the phase offset (coarse delay) affect the jitter?
No. The phase offset, or coarse delay, adjustment on the AD951x is a function built into the divider for each output. Depending upon the selected divide ratio, there are from 2 to 32 edges of the incoming clock which can be chosen as the trigger edge for the output. This allows for setting a phase offset, or time delay, between outputs. This feature is entirely contained within the divider block itself. These dividers are designed so that this feature does not affect the jitter of the output. The jitter performance of the output will be the same regardless of the phase offset (coarse delay) selected.