Several times now I've tried to jump to a star within my ship's jump range but it refuses to let me jump straight there. The game is instead plotting two jumps, with the first being almost the entire distance there, then the second just a small hop to complete the plotted course. Is this a bug or have I just missed something obvious (or even mechanically hidden)? I have more than enough fuel as the attached screenshots will show, about 80% of the tank left and I've made further jumps than the entire plotted distance prior.
I've seen this before and it's something to do with the boxel data structure and the routing algorithm. It's optimised to find you a route in a reasonable amount of time. Something about boundaries between boxes often results in shorter than max range jumps. I can't pretend to know exactly how it works inside but it does that. For jumps inside your range don't bother plotting the route just select the target system. You'll often find inefficient jumps in longer routs and you can often just skip past them. It's a quirk but I suspect it's a trade off for finding a good enough solution in a short enough time.
If you just want to make one jump to another system, you can merely select it in the galaxy map (with the "select" icon on the right) but not plot a route there. That will allow you to jump there directly regardless of anything, if your ship has enough jump range.
(This is the standard way of doing extra large jumps when your FSD is supercharged.)
(This is the standard way of doing extra large jumps when your FSD is supercharged.)