Harmy said:

But I think it would be a bad idea to use all 3 separation masters, because it would mean combining 3 different film strips together, thus combing four different grain patterns (that of the o-neg plus one for each of the seps), so the sep-masters combined would have to be 3 generations worse than the o-neg and that's assuming they were stuck directly from the negative.

Didn't they use the separation masters for the Wizard of Oz, and before that The adventures of robin hood.

Warner Bros and MGM i mean.

Sleeping beauty also was restored from the 3 strip separation masters ycm.

As were portions of star wars special edition in 1997 in which the negative was too far gone to use.