OK, let's look at the highest demand attractions, getting to 10 across those 3 parks:
Yes, you could argue for other things like Pan, Pirates, Mansion, Dinosaur, etc but I think that's a reasonable enough list. Assuming an hour of travel time and an hour of eating time (both conservative) It's still a pretty big stretch to hit up a lineup like this in 4 hours.
- Rock 'n' Roller Coaster
- Tower of Terror
- Toy Story Mania
- Star Tours
- Seven Dwarfs Mine Train
- Space Mountain
- Splash Mountain
- Big Thunder Mountain Railroad
- Expedition Everest
- Kilimanjaro Safaris
I'm sure @lentesta could come up with a touringplan to do all this fairly easily in a day, but cramming it all in a 6 hour VIP tour seems extreme.
Yeah, that was my thought as well. That's gotta be a whirlwind trip.
Even with backstage road travel (presumably they won't be going through the main gates after you enter the MK for the first time that day), that is a lot to hit and quite a distance to cover. I mean, they would have to plan that like a marathon - for instance, van parks and you enter at the backstage entrance next to Star Tours (you can drive right up to it), do Star Tours, then Midway Mania, and then cross over through the park to RnR/ToT, and then the van is waiting for you at the backstage road there. Doing stuff like that is the only way I can see this reasonably accomplished.