One final test: level 20 dungeons versus FATEs.

Level 20 dungeons: Halatali
Time: 39 minutes
EXP: 39344
Experience rate: 1009/min

Level 20 FATEs: South Shroud
Time: 22 minutes
EXP: 48972
Experience rate: 2226/min

That FATE-farming went exceedingly poorly. I died repeatedly and got no reward for two FATEs (including 10k from Coeurl King). Worth reproducing here even for that alone. Didn't turn out well at all, but it still beats the hell out of dungeons. I did another level in FATEs, which went much more smoothly:

Level 21 FATEs: South Shroud
Time: 18 minutes
EXP: 61405
Experience rate: 3411/min

That actually ended right before Coeurl King, so 2 minutes later, I had another 11000 EXP. Wouldn't be fair to include it, however. Regardless, just beating a dead horse.