I'm trying to get a decent IV, Careful natured Registeel in Emerald. (Seismic Toss tutors ftw.) I heard synchronizers don't work on stationary Pokemon in Emerald, though- can anyone confirm/deny this?
This is true
Synchronize does not work on Stationary or roaming Pokemon.
Source: http://bulbapedia.bulbagarden.net/wiki/Synchronize_(Ability) (scroll down to ouside of battle)