Oh it's very doable and not as difficult as you may think. It takes quite a bit of planning in some parts (namely for Evrae and BFA) but the basics have to do with overdrives (especially Rikku's) and having the right equipment, First Strike on a weapon is essential.

The most annoying part is not having Flee and watching your characters constantly refuse to run away.

There are much harder challenges out there, though I'm not 'hardcore' enough (read: dont have the time) to attempt them. A NSG game is a nice change up though if you've played through FFX numerous times and are looking for something different.