So Plasmid's beautiful algorithm guarantees a maximum number of moves when the weights, expressed in an odd ternary notation, are
RLLLLR
That is, the 243 and the 1 are in the Right pan, while the U and all other weights are in the Left pan. In this case, there are 4 triple moves (move from Left to right, remove same weight, move same weight back to Left) and 2 single moves (Left to Right). Actually, since Plasmid starts with RLLLLL, there's only one single move.
So this algorithm has a maximum number of moves of 3n-5, where n is the number of weights.
The algorithm is so clear, and solves such an important problem, I'm happy to declare that as a solution.
So, my next question is: what is the algorithm and max moves from a LeMans start--empty pans?