It really is a great feature to work with.
With use of RNAV and RNP STARS, Enroute, an initial/intermediate legs, it allows ATC to manage on set of waypoints with an offest. The ac will fly it perfectly.
As noted, if you are RNAV or RNP, and you need to deviate for weather, offsets are a great way.
Unfortunately, different ac configurations handle offset differently. With the 777, you are limited the min offset of 1 nm, which is great for enroute/STAR, perhaps initial, but intermediate segment is tough.