The tyres are directional so you can only do front to back on the same side. I have never rotated tyres and never has issues, it is just some people prefer to do it for the sake of it.
Fisher didn't specify what tyres they were, but it is a good thing to highlight as I made that mistake before as I went to put tyre dressing on them after I had torqued them all up...
Rotating tyres helps check for issues like nails, screws etc, confirms they are wearing true with no issues to the alignment or pressure & helps to extend the life of the tyres as typically toward the end they wear faster.
It's easier to rotate them if you swap alloys out for a winter set up, otherwise it's a bit annoying especially since everyone may not have a proper trolly jack to use.
