As far as I have understood, you need only to beat the strength, not the whole intensity. Points used for duration or range does not count. At least, it was this in RQIII. And a Strength 1 Duration 15 spell can occur. For instance, cast Logician 1 for 1 season on somebody helps him with +10% on all lores ... and forbids him all augments for 1 season. It reminds me on casting fanaticism on a foe before he can cast all his spell: That meant no protection, no fireblade, no bladesharp, ...
I am not doing anything, because I was not the OP, nor a GM, but I can see this occurring: My character is a sorceror, and I may find myself having a dominate spell without having learned the corresponding summon. In that case, it CAN occur, and I easily see my GM using the opportunity.