Literal and legal hashing of the rules aside (I get enough of that at work writing special notes and provisions in construction contracts and plans) I think one can easily choose to go the route of common sense here and make two observations that work well:
1) The x2 Lore restriction just makes sense for potions AND enchanted items. At least to me. If it does for any of your reading this as well: USE IT. Problem solved, game works well with it (I use it in my game) and it makes good sense.
2) The alternative is to use my ever useful rule-of-consequences for dealing with players creating massively powerful things. Be it rituals, potions, or magic decoder rings of DOOM, when one pumps a lot of magical-mojo-go-juice into anything they are quickly raising their own profile on the cosmic mystical radar screen. The bigger that profile becomes, the bigger and nastier are the things that will sit up and take notice. This is true and constant throughout the Dresden novels even. Any time someone starts working up a large, nasty, powerful ritual of some sort (Nicodemus and his Shroud of Turin Ritual of the Apocalypse, the Exploding Heart Kung-Fu Ritual, Kemmler's Deathly Hallow Rule the World as a Necro-God Ritual, ect... ) things quickly get complicated for them as more and more power players take notice and become involved. Fae stick their fingers into it. Swords of the Cross stumble into it. Wardens start poking around. Harry and crew get drawn in. Denerians start running around. The Archive knows what you are doing since you have probably written something down. Oh, and do you think Odin gave up that eye just to completely miss some mortal wizard casually throwing around 100 plus shifts of magic in his mom's basement? Or that the Gatekeeper isn't going to get all curious; especially as, I am sure, no end of Outsider related nasty is going to notice at some point and try to take advantage.
If it was easy and simple to just sit back in quite, pump up something HUGE like a ritual or magical item with 100 plus shifts and then keep it handy "Just in Case"; you would imagine that everyone and their mothers in the supernatural world would be packing around these massive, military-grade magical bombs. But, they're not. OH, they may have something tucked away in their home turf. Hidden behind some magical wards and such. All hush-hush. Which is why in the supernatural big-league (MLSN?) home turf is so valuable. But, even the Merlin is not walking around with a belt full of 100-shift potions; and if anyone could, it would be someone like him.
And the reason is that the complications created by lugging around a giant beacon of magical power and the resulting effort needed to defend said beacon of interest is just not worth it.
So, if alternatively, if you don't like the x2 Lore ruling on potions (or have players that really want to go to town as a crafter or ritualist as well), then let them have their way. Then, hit them with the consequences of having it and eventually they will understand that having said massively powerful thing quickly consumes their whole characters life.
I know, not a logical win using literal interpretations from the rules; but it works.