A little while later into the area i encountered a second Juggernaut, and this one was just wandering about. The first big area of Chapter 11 was stuffed with huge non-boss monsters i wasn't supposed to be able to deal with yet, but i hadn't encountered any in this area so far, so i started wondering. A couple google searches seemed to indicate that it ought to be possible and gave a few hints. First i tried swapping in some elemental resistance items, but that wasn't quite enough. Then i swapped Sazh into my party (replacing Vanille) and spent the > 200,000 CP he'd accumulated on the sidelines maxing out his Synergist job. His stats were still a fair bit lower than Vanille's , but adding his buffs on top of the elemental resistance was finally enough for me to win the fight. Not quickly or easily, i got zero stars in my ranking, but i won it. So after a little bit of internal debate i decided to go back and beat the first one who was part of an event. Juggernauts aren't worth much CP for the amount of effort involved, and although i'd noticed while doing my research that the reward for beating him was a new item i didn't have one of yet, it wasn't a spectacular item. But i decided to do it just for the sake of completion.
So after having spent at least an hour, quite possibly two, trying to beat the Juggernaut and failing, then doing some research and eventually succeeding, i then spent probably at least 15 minutes backtracking to the first location. I fought the first Juggernaut, died once because of some bad timing, and then beat him on the second attempt. I got my reward, and i believe ended up equipping it on Vanille for a marginal benefit. Then i figured i might as well check the item type and add it to the list now.
I've been compiling a lot of data on the item upgrade process. One of the things i've discovered is that items have a distinct type that determines how much experience they get from each component. When i first started charting out the weapons i found four different types. When i went through the accessory lists i discovered three more types. That gave me seven types total which formed a very nice pattern... with two gaps in it. One of the gaps was kind of small and could potentially be dismissed. But one of the gaps was huge, there was a significant jump in value for pretty much every component in the list. There was little i could do about that however except continue playing and see if i ever found anything to account for it.
I'm sure you can see where this is going. I opened up the upgrade menu, selected the brand new accessory, selected my primary index component, and there it was, right in the middle of the gap where i'd predicted something ought to be! I quickly charted all the other components for the newly discovered type, and everything fit perfectly. There's still the much smaller gap, but i'm pretty sure that's just an aberration in the component i'm using for indexing. And of course there's always the chance that there are some rare/late game items that will extend the sequence in either the positive or negative direction. However i'm still inordinately happy about having beaten that Juggernaut just because it confirmed what i'd been expecting out of the blue. I love it when math and reality collide in exactly the way i expected :)