The more I think about the building block, the more I nod like an insufferable know-it-all.
Which is cheating, because a) I wrote the darn thing, and b) the fact that I'm thinking of reasons it works AFTER I wrote it means I didn't think of some of those reasons before I committed to drawing it, and it's not THAT hard to make up reasons why a metaphor works after the fact.
NONETHELESS, behold the building blocks, and their helpful metaphorical information!
To clarify, Tedd has taken elements from many separate spells, and merged them together to make singular spells.
In those cases, however, Tedd is crafting a new spell, and making them available to cast by using wands.
What Tedd is thinking about here is casting two spells as though they were one spell without creating a separate new spell.
For example, Tedd mastering the "Foxy" spell and the "Duplicate" spell, and making a wand with a spell that combines the effects into one spell, would not be the same as what Nanase just did.
If, however, Tedd put each of those spells into a wand as separate spells, and Tedd combined them while casting, that would be almost the same as what Nanase just did.
I say "almost" because, as Tedd points out, there's the x-factor of a wand being involved, so it's at least a little different. But for most intents and purposes, it would be the same thing.