When we were there Jan. 2011, my daughter was 7 and was not allowed to ride Dumbo or BTMRR by herself. It did not matter if she met the minimum height (which she does since she is very tall for her age). Both CMs told us that it was age 8.
I would bet that that CM heard it wrong. Like when DS was little and I belonged to two zoos, and I just couldn't get it in my head which zoo he was free at and which he wasn't, b/c one said "age and under" and the other said "age and up". I was a bit wobbly in my head already (turns out my iron was drastically low...once it came back up I got more of my brain back) and it just confused me. Or when people think a child can be a lap-baby on a flight for the range of "2 and under", when the reality is that as soon as the child turns 2 they cannot be a lap-baby anymore. (watched mass confusion by flight attendants who let 3 2 year olds sit on laps, with no seats reserved, because of this problem...I don't like the lap-baby thing (after doing it with my wriggly son) but was a little jealous of how much those other moms had saved, when we all had 2 year olds!)
When we go October 2013 - oldest DS will turn 14 one month after we get back. We were planning to let him and DS9 go around the park on their own (same park that we'll be in AND with various times they have to meet up with us throughout the day) armed with a cell phone. Since he's not 14, does anyone see a problem with letting him and his younger brother walk around together without us?
I think it's fine. I imagine that IF DS wants to wander alone at 12 or so, we'll probably let him. But that's a big IF because we do love our family together time! But we have time, he's just about to turn 8 and his attitude will surely change, LOL.
Okay, I must REALLY be protective or something. I wouldn't let my 13 year old ride alone. I barely let my 9 year old go to the men's restroom alone this trip!
Though, after seeing him this trip, the 13 year old would do great touring alone...though I'd miss him terribly and seeing his...well, non-reaction. LOL
I bet that if you didn't like riding the rides; if you got sick or whatever, you would let him do more. You just like the FAMILY part of the family vacation.
For some rides, we are HAPPY to let DS go alone. At Universal when he wants to do Flight of the Hippogriff literally 15 times in a row, "go for it, dude". Same with Woody Woodpecker's Nuthouse Coaster. "Go, spend an hour riding it...just don't run, I can see you!"
And the teacups, sure, fly, be free!
But most other rides, one or both of us still
wants to ride that ride, and so we've got family togetherness.
I think what Figmant was alluding to is that there are two separate height requirements for the Speedway, which makes it unique. One height is to ride at all, even with a parent, and the other height is to ride alone.
The taller height mainly just means the kid can push down on the pedal fully. DS is about 52" now and at least on Autopia at
Disneyland can *touch* the pedal, but can't push the pedal, let alone push it all the way. I wish they'd state it that way.
Boy am i confused

When we went in August my then 5 1/2 yr old who is 48 inches and 7 1/2 year old son who is 54 inches rode on SM in the same car with me. She rode on EE with me and he sat alone, same with BTMRR.
Riding alone is different than sitting alone.
