Had 5 minutes or so to spare this afternoon, so I got to working out a non-trial-and-error method to solving the Roadblock puzzle, of course neglecting crazy stress, the rule about pencils and a bad memory...
The 15 items are:
Leg 1: Donkey, Tandem Bike
Leg 2: Pole Vault
Leg 3: Camel Milk
Leg 4: Chicken
Leg 5: Stilts
Leg 6: Rowboat, Musket
Leg 7: Blackberry
Leg 8: Propane Cart
Leg 9: Cleaning Man, Flowers
Leg 10: Teacup
Legs 4 and 8 each had a U-Turn. We'll assume we don't know where the bike (single-seater) belongs.
The rules are:
1 item from each leg,
1 U-Turn,
1 mode of transportation involving sticks,
2 items brought to or found at the Pit Stop,
2 modes of transportation with wheels, one of which was used at a Detour and
3 animals or animal by-products
1. The first thing to do, as each team did, is to put up the U-Turn.
2. Next are the legs that have no alternative option (Sudoku!): the Pole Vault, the Camel Milk, the Stilts, the Blackberry and the Teacup.
3. Hmm, we have both the pole vault and the stilts, but only one stick-transport is needed. That means the bicycle (which we left out of consideration earlier) would have to replace one of them. Now there was a bike in Leg 2 but not Leg 5, so the stilts (Leg 5) remain and the pole vault is replaced with the bicycle (Leg 2).
Current items: U-Turn (4 or 8 ), Bicycle (2), Camel Milk (3), Stilts (5), Blackberry (7), Teacup (10)
4. Only two Pit Stop items in the list, and that's the chicken (4) and the musket (6).
5. Since Leg 4 is filled up, the U-Turn belongs in Leg 8, eliminating the propane tank cart.
6. With the propane eliminated, there remain only two modes of transportation with wheels: the bicycle for Leg 2 we have already selected, along with the tandem bike for Leg 1.
Current items: Tandem bicycle (1), Bicycle (2), Camel Milk (3), Chicken (4), Stilts (5), Musket (6), Blackberry (7), U-Turn (8 ), Teacup (10)
7. Well, we do need three animals, so with the milk and the chicken, we do need the cleaning man (9), whether he is considered an animal or not, to fulfil the set.
Current items: Tandem bicycle (1), Bicycle (2), Camel Milk (3), Chicken (4), Stilts (5), Musket (6), Blackberry (7), U-Turn (8 ), Cleaning Man (9), Teacup (10)
Task complete!