You won't be loosing all that much xp though. That is, if you are doing it right... as in not sitting there grinding it out for just the base xp per synth plus your food and FC bonus. Leves will shoot you through your levels at an accelerated pace.

Also may want to look into your GC's training manuals as well if you haven't already. Then there's the rested bonus...forget if DoL can take advantage of Armory once you get a craft to 50. Either way, you are missing a lot of potential if you are relying solely on that 10% and 3% to accelerate your leveling.