Years ago, I went out riding a group of maybe 10 people. Out of all of us, my sister, one other girl, and I could ride, everyone else was new to it. As we're riding, this a girl's horse shoots off and she starts screaming. The horse is galloping at full speed and she's just holding on for dear life. I got my horse going, caught up to her, got slightly ahead and slowed my own horse down in front of her, and hers just followed suit and slowed down with me.  I told her that I knew she was having trouble controlling her horse, but to try to stay next to me and like a foot behind and that hopefully her horse would takes cues from mine, and we rode real nice and slow all the way back. When we got back to the stables she told a guy there what had happened, and the guy (who wasn't trying to be a dick, but sort of spoke without thinking) told her "that's one of our tamest, most gentle horses, but they kind of know if the rider knows what they're doing or if they're can't ride worth a damn. If the rider is not in control they'll do whatever they want, sometimes." The moral of the story is: If chubs is nervous and inexperienced, she may end up falling on her already crappy hip.