I actually don't really agree. From all the medium-large sized business I've been on the inside of, as both a consultant and employee, it seems that a lot of people have a lot of pretty OK ideas about how to fix things within the org and where to take the products. In general, excluding a few noobs and whack-jobs, these ideas seem to be about as viable and plausible as the ideas that actually do get pushed down.

The valuable thing in a big company isn't the idea; it's the way the idea is executed. You'd be amazed what kind of nonsensical ideas will work if your team gets it just right.