I've acquired a copy of Ancient Magic very recently, and I'm currently working my way through it. Apologies if this is explained later in the book, but I've made my way through a few chapters and I'm still scratching my head.
As I understand it, to begin working on a breakthrough, you need to find a Source of Insight. And then, after some pondering, with any luck your mage will come up with some Insight. The rules then state that "a single source can generally only provide a single Insight" (admittedly it does then say that there may be rare exceptions) [p8]. The insight then gives your mage an idea for a specific effect. After you've created that effect, you gain breakthrough points equal to the magnitude of the effect, huzzah.
The rules then state that "[the mage] must find another source of Insight before repeating the procedure" [p9]. Does this mean that you have to find a completely new Source to gain any more breakthrough points towards that breakthrough? Considering that, for example, the integration of Canaanite Necromancy requires ~45 points, that's 45 magnitude's worth of effects [p31]. The suggested effects that you could gain are all <8 magnitudes [p32,33], so one of those is only going to get you less than a 5th of the way there at best. Considering Zephaniah is the only proposed Source given for Canaanite Necromancy, how are you supposed to complete the breakthrough? I suppose you could round up a bunch of apprentices, have Zephaniah teach them all, and count them all as separate sources of Insight, but that's about it.
Am I misunderstanding the rules? Can you keep reinventing duplicates of the effect to keep gaining breakthrough points from the same Insight/Effect, p31 seems to reinforce that this isn't the case? Or should the Storyguide say that Zephaniah is perhaps a rare exception who can provide several different Insights towards the same breakthrough? Or is it intended that the Storyguide will come up with additional sources of Insight?
As a disclaimer, I'm aware that HoH:TL has rules on Original Research, though I'm not familiar with these. Also, it may be that an excellent worked example appears later in the book. I could wait for this, but I wondered if someone might help relieve me of my confusion before then. Any help appreciated! And if anyone has advice on using these rules for a saga of ambitious relic-hunter mages that'd be great! Thanks in advance