A doubt for ReCo GLs in A&A p.57

Hi all people,

do the GLs for ReCO spells need a minor Breakthrough as noted in the box (A&A p40)? I do not understand if to induce the symptoms is the same of invoke them!

I am sorry for this very noob question!

I believe the breakthrough is only necessary if you wish to do mentem effects with rego corpus spells.

Tweaking the target's humors to create symptoms in more of a blunt instrument sort of way I would allow without any breakthrough. (Although the symptoms would only persist for the duration of the spell).

Is that the question that you had or did I misunderstand you?