Not probable but possible......we managed to do this during an EE day at MK but you have to hustle and involves lots of walking
To be done by people willing to walk only - DH (me) did this to show DW (for a joke) how to go logistics crazy at WDW commando style for a morning and to get DS all the rides he would like
Right Away at 0800 Get FP for Winnie - return time 0900-1000
Do some rides, get FP for Buzz - return time 0925-1025
At 0925 get FP for another attraction - in our case Peter Pan return time 1005-1105
0930 Rode Buzz Lightyear then walked up to Winnie, rode using FP and then checked out the Winnie store at the exit and then rode Peter Pan
In the meantime, taking DS on rides like Dumbo, Madhatter, Small World, Snow White, Tommorowland Indy Speedway - DW took DS on some of these whilst I gathered the FP's up. I took DS on some as well and we did the relay on Madhatter - I rode with DS went to the exit and then passed DS to DW for a 2nd go on the ride whilst I went to get the FP's
I would not recommend the above approach due to its tendency to make the trip too much like a strategy but it can work
Below is a good link for fastpass info
http://laughingplace.com/info-id-wdwfastpass.asp
Man, I did not have to worry about what I was eating with that back and forth walking....
Thanks
Jason
