"Copy Newer" and "Copy Different" ???

[dnanian]

The thing is, it just doesn't seem like the situations you describe are going to be very common at all, don't you think?

The vast majority of the time, people use Smart Update (as opposed to Copy Newer), and Smart Update does use Copy Different as its base algorithm.

The reworked description makes the concept of modification time clear, but I think going into more detail brings up some details that require a pretty thorough understanding of Unix to "get" -- something that most of our users don't have. Hopefully, those who do worry about this rare situation will take the time to ask, experiment, or read this forum!