Sixth Excellency and Craft abilities- Is this as awesome as I think it is?

Question

Alchemical exalted have an array of 'extra' charms compared to other exalt types. One of them in particular is evading my understanding. You pick it for an attribute/ability pair (say, strength+athletics or wits+awareness) and when rolling that combination you treat that ability as if it was at its maximum. (So, if I have wits 5 and awareness 1, then any wits+aware rolls I make are treated as if I'm using wits 5 and awareness 5.) The two major downsides of this are A. you can't use this rating to qualify for charm prerequisites, and B. this only applies to the one pairing. (So, if I wind up having to roll Perception+Awareness, then I have to use Awareness 1.)

My question is, can I use this to get cheap ranks in craft skills? Buying a charm costs alchemicals 6xp (plus 12xp for the charm slot, which is generically useful) and buying a skill up to 5 costs 27xp* so if I can do this, it's very worthwile. I can't find any charms that require craft as a prereq so A isn't a problem. If I needed one, buying a single craft skill up to 5 isn't too harsh. (Craft is subdivided into 5ish different subskills, but you only need one to qualify for charms.) It's very rare in my experience to roll Craft with anything other than Int, so B won't be a problem.

I'm planning to play a techie focused character who's hoping to have decent ranks in all craft skills plus maybe some of the special ones like Craft(Magitech) so we're talking about at least 45xp difference here. If I can pull this off with no repercussions (other than my Storyteller smacking me with the rulebook, heh) then that's awesome. If there's repercussions that I've missed (A max on simultaneous charm slots? An important time when you'd roll another attribute with Craft?) but this will work, then information on the drawback is useful. Then again, this might not work for some reason I'm overlooking.

Summarized question: Is using the sixth excellency on every single craft subtype legal, and if so, are there drawbacks? If it is not legal for some reason, why? (And while it's not the main point of the question, if I've miscalculated and purchasing the ability points is cheaper than purchasing five slots+excellencies then that's going to get at least an upvote. I doublechecked the calculation, but that's not to say it's obviously correct.)

Bonus points for factoring in optimal spending of points during character creation, which uses a slightly different economy than during play.

*3x for the first point, then (2 times rating)-1 for each additional point. (-1 because it's favoured.) 3+3+5+7+9=27.

Answer 1

Ok, Firstly, (Int + Craft) alone is only going to be useful in repair and diagnostics. If you add in (Perception + Craft) then that should be good for everything that doesn't include fine by hand details. In short you could design and build a dirigible but not a finger thin automata scout. Adding (Dex + Craft) would add in the find details of course.

Secondly, to quote the book from with in the text of the charm you're asking about "In the case of Craft, installation covers all possible actions involving all possible Craft variations in conjunction with a particular Attribute." So yes, while three purchases of the sixth augment in respect to the above listed Attributes will cover almost all of your crafting needs, your ST may choose to throw a book at you. I would definitely consult the ST before attempting to use any craft besides the five elemental crafts and Magitech, as Genesis is heretical in Autochthonia and only your ST will know how his Autochthonia feels about Craft Fate (within the Designs of Autochthon, rather then the Loom of Fate), Nercotech, or any of the more obscure Crafts.

Thirdly, to address one of your questions posed; I want you to recall that you do have a max on simultaneous charms as an alchemical, as you can only attune to your installed charms with your personal motes. Each sixth augment cost one mote of attunement and as such there is of course a limit.

Fourth and Finally, some minor downsides/opportunity costs:

• Recall that you can't buy natural specialty dice unless you have a rate in the craft in question
• On the flip side, you might be spending 3xp per specialty dice adding a specialty to all three of your 6th augments for craft
• If you ever need to uninstall your sixth augments, your crafting suite of other charms also become use-impaired
• If you're doing a high Clarity build anyway, having 5s in every craft you're using as opposed to 3s will only become useful after you purchased and installed the charm Technological Analysis Engrams, as you can easily exceed Ability ratings of 5 with use of the charm Clarified Data Assimilator