My magus is going to try and find a Theurgic Spirit Familiar. Under the description of the virtue, it says that the magus must prove his worthiness and that the rule of thumb for this is that the (Tech+Form) proposed for the bond must be at least twice the might of the spirit. My question is this, is this literally just the Technique + Form, and not the complete Bind total?? Also, does an appropriate focus come into play and modify the Tech+Form total?
The rules as written specify just Form and Technique. Strictly speaking, that's the way it is. However, I would allow an appropriate Focus to be included, because that adds a Form or Technique. If a player asked me, that's what I'd say, and it makes sense to me. If a player wanted to include his Intelligence and Magic Theory, I would accept that, no argument. But the bonus for a good aura? No, because the Aura isn't about the magus being worthy. A lab that's great for binding familiars, or for an appropriate Art, or just in general? Again, and especially, no.
Without having read the section at all...I'd say just Te+Fo, otherwise it'd have said "Lab Total" or "Binding Total". I'd count a relevant focus into that figure, since foci apply when arts are used.