They'd probably be your NPC's. The summoning/animation doesn't take very long, but that doesn't have to mean the duration of the spell is as short. Actually I'm not quite sure how that would be treated, is it a duration 1-2 for the summoning or is that also the lifetime of the summoned creature? Would probably make sense to make a spell summoned creature live as long as the duration, while a ritual summoning would last longer or even be permanent.
No no no no no. If you are summoning (as opposed to creating) a creature, the summoning will be very short. The
control is what sets the effective duration...Unless you, say, summon a troll into the middle of the gatehouse and don't
care about controlling it.