Official comment
When you're mixing, the deck selected as "master" will switch automatically based on several criteria (such as whether or not that deck is still playing, or you've entered a loop). When that happens, the master will switch from one deck to the other. What happens then is the new master deck would require you to move the hardware fader to match the position of the software fader, as the sync may have put it in a different position.
For example - deck 1 was the master playing a 128BPM track, deck 2 was the slave playing a 126BPM deck. The pitch faders for both were at 0%, but you pressed the sync button for deck 2, meaning the software pitch of deck 2 is now at +1.59% to match. But once deck 1 stops and deck 2 becomes the master, moving the pitch fader on deck 2 will do nothing ... until you go to the +1.59% position to "pick up" the software fader to move it. Only then will any other movement affect the actual pitch of the deck.