I'm very close to beating FFX-2 with ALMOST 100%. The only thing I missed was that I accused Rin instead of Rikku. Damnit. So I got an Episode Concluded (rather than Episode Complete) for Mihen Highroad.

My question is, how thorough do I have to be on the second playthrough to get 100%? Can I completely ignore all side-events except for viewing the correct scenes in Chapter 4 for Mihen Highroad? Or do I have to do everything for Mihen all over again in order to get the Episode Complete there?

Similarly, if I want to get the Mascot Dress Spheres on the second go-round, do I have to do everything 100% all over again or will my previous Episode Completes carry over, allowing me to just focus on completing Mihen Highroad successfully?

And finally, how long would you estimate a no-side-quest New Game Plus playthrough would take? I'll probably finish my first runthrough at about 50 hours, but it seems like 90% of that has been side-quests. Would it be unreasonable to think that I could run through it a second time, ignoring everything but the main plot (except Mihen as mentioned above), in under 10 hours?