Question about Mental Stress and Sponsored Magic?

[Tedronai]

Or is Conviction used on speed-thaum instead of Lore and I am just confused here?

"Thaumaturgy with evocation's speed and methods" is accomplished as evocation save only for the effects available.
The resultant spell is measured in Power, not Complexity.
Power is based on Conviction.
Each casting requires at least one mental stress, or more if the spell's Power is greater than the caster's adjusted Conviction.
etc.

[Todjaeger]

It could do that, too. I feel (according to the rules and the game developers' comments) that the magic system is a little more fluid than some may figure.

I'm certainly not recalling a hard rule about being unable to increase the power of a spell with Aspects, but I am open to the possibility that I'm wrong.

From my memories of the playtest, it was possible to use character Aspects to modify the Conviction roll when providing a power source for an Evocation spell.  As currently written (admittedly, how I read it) that area where the play test allowed use of Aspects to 'boost' Conviction for the purposes of casting an Evocation, isn't available any more.  Aspects can definately be used to target or control the power for Evocations, or in Thaumaturgy to determine/raise power, as well as handle complexity.

Given that there was that kind of change between the playtest rules and how Evocation spellcraft is currently written, it looks like the Power for an Evocation is limited by a character's Conviction, as well as foci and specializations effecting power/Conviction.

-Cheers