A recent trip to Disneyland was my first time since learning what the Goat Trick was and how to do it, so of course when I road Thunder Mountain I asked the CM if I could ride in the back and they told me I could. I got to sit on the far end in the farthest seat back, basically the absolute best position for the trick. Having no idea what would happen, I went down that second drop keeping my eye on the goat, twisting around to keep it in view until it was impossible to see and, wow, it was really weird.
It's really hard to describe the sensation in words, but it kind of feels like being flushed down a giant toilet. It feels like you're being sucked into a giant vortex or whirlpool or something and the g forces are like nothing else inside the park. It also stays in view for an unimaginable amount of time...you're like 180 degrees from the lift and down pretty far and you can still see it. It was REALLY fun and I'd like to thank you guys for bringing that to my attention.
I rode it again at night and although the drops and sounds were ultra scary during nighttime, the ride turns into a near Space Mountain since you can't see anything and the goat trick was extremely hard to pull off. Since the rear is dropping by the time you see the goat, you have to pinpoint it right away and that was made difficult since it is not lit up. I had trouble finding it and staying locked on it so it's definitely a daytime trick.
I strongly recommend asking the CM if you can sit in the back and try this neat trick, it really does work.