TOPSwitch-HX variable frequency mode & EMI

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I don't understand why TOPSwitch-HX, in variable frequency mode, turns off frequency jitter. This action will increase EMI when operating with certain loads, it isn't? Thank you very much for your assistance.
When TOPSwitch-HX operates in variable frequency mode the primary switch current is held constant, so varying the frequency (more specifically, off-time) becomes the manner by which the output is regualted. This does not allow frequency jitter because it would interact with control loop. Normally this should not impact EMI since worst case EMI is usually at higher output power levels. Variable frequency operates at lower power so EMI will also be naturally lower for this reason.