Just because it doesn't happen to you doesn't mean it's non existent. I've had lag issues when my net is perfectly fine on some instances during the game and it's usually after their patches or someone else I know will have it, but it doesn't affect me until a few days later. It's there, it's like the 90k error that happened before the last patch, I only got it once when many others were getting it about 10-20 times a day.
Edit: The thread below might shine some light on the issue.
http://forum.square-enix.com/ffxiv/t...-fix-something.