It might save you time cherry-picking some objects to scan in a system but I don't see how it will make scanning a system any quicker.
Oh, it's definitely for cherry-picking. Like many others, pre-1.3, we've adapted different approaches to finding what we want to scan. Like the inner-most planet snuggled between two asteroid belts. It's a quick flick of the 1 key and toggling down until a planet hologram shows up. Or the fifth and sixth planet have water/ammonia features, but they're on opposite sides of the star in their orbits - measuring AU doesn't quite work when you travel to the first of those interesting planets (I tend to measure AU from the star, note where they are on the "radar" map, and plot a course dependent upon the results). Then, there's the "high above the plane" approach.
I'll probably use the feature sometimes. Most times not, as pre-1.3, the approach I'm using now works fine.
Hoping 1.4 will cure the "real life shinies" that usually result in me face-planting a neutron or white dwarf. Television, wife aggro, kiddos. EDevs, can we get a toggle switch to turn those off?
