For years the official rule was anything bigger than a K-28/K-37 combination had to be split crossing Lobato and Cascade Creek. There are photos of a K-28 leading a K-36 cross Cascade Creek, and later on the same combination doubleheading a fan trip across Lobato.
Sometime in the 1960's, the rule was changed to prohibit all doubleheading across the two trestles.
Today's practice would be determined by how the restriction is worded, which could be changed by proper authority (Superintendent, Trainmaster, etc).
463 and 497 have been on Lobato Trestle together at least once in modern history. But we won't talk about that.....