Now can we learn Knock book and gain its scrap in one turn? Perhaps if we boost roll with Lantern influence? Or would we gain a scrap from studying Level 2 Knock artifact? Can someone remind me rules for studying artifacts, does they take one book slot in study action or is that separate action? Do we gain any Lore scraps from them? Also I think deciphering rules changed at some point. Does deciphering counts as reading now?
In order:
1) No, we can't get a scrap from studying the Knock 2 artifact, since it's below our Knock level, but we can gain scraps from other artifacts as long as they're equal to our Lore level or higher (e.g. studying the Lantern 4 artifact would give us 1 Lantern scrap).
2) We can study two artifacts, one artifact and one book, or three books in a single study action.
3) Deciphering counts as reading now, yes. So we could e.g. study the Lantern 4 artifact and attempt to decipher the Knock book once, or try and decipher the book three times, or try and decipher it twice and slot in one of the low level books we still have laying around into the last slot, for example. And we'd read the book as soon as we finish deciphering it.
Necromancy would be much more palpable to the player base if it was not angry Wolf touched spirits. If anything we should focus on how to calm those spirits and send them where they where supposed to go. Would also deny them to other cultists. Exorcist Velvet for the win! If we learn how to call on normal spirits of dead in the process even better.
Necromancy isn't the problem, it's the fact that the sacrifices have to still be alive when you sacrifice them for it to work. If we just had to sacrifice dead bodies to summon them, it'd be (mostly) fine! Inconvenient, but fine.
Edit:
I realized another argument for going for the Knock 5 book for the scrap instead of a DoA lesson besides "could get a trait" - our Wrong Keys expire at the end of T20, so if we e.g. wanted to have DoA give us a Knock lesson this turn, then a Knock Influence next turn so we can try and punch through the Sacrament as quickly as possible, we'd have no Wrong Keys available for T21, T22, or T23 (for DoA's resummoning). With that in mind, I think I'd prefer the book over the lesson.