Will level sync be allowed to be activated freely (not just automatically, as in the case of instanced dungeons and FATEs).

My husband and I do all our quests together, and will be playing through all the new quests on our 1.0 characters. I have some level 1 classes I've never played to choose from, but he does not have any left (each class has been leveled somewhat). Will we be able to freely activate level sync so that we can play together and I can catch up to him without a penalty while questing, doing leves, and other leveling content?