Actually, I can think of a way, but it's probably still an engineering nightmare.
Ever notice how in the stations of suspended coasters (at least Iron Dragon at Cedar Point, the only suspended I've ever really LOOKED at), there's a pair of guide rails to keep the cars from swinging while the train is in the station, and under the cars is a small knob (for lack of a better word, I've never gotten a GOOD look at it) that fits in this guide track.
Well, what if approaching the loop the train went into a set of these guide rails that follow along the loop -- the train wouldn't be able to swing while in the loop...
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Coaster count: a meager 33, but climbing this summer!