Why TARAN does not calculate and display more information about groups?
Indeed, the only information displayed about groups is:
1. Extreme spread
2. Average point of impact
Why don't I display more? Because I don't want to display bullshit.
Usually, the number of shots in a group is statistically insignificant to pull any conclusions. On "teh Internets" I have seen people thoughtfully reflecting on the form of a five-shot group ("well, it's a bit oval, stretched from top-left to bottom right") -- they call it "group analysis", what a load of crap!
This being said, ES and average PoI of a single 5-shot group are just as insignificant as any other 5-shot "statistics" -- I only display them because people love them so much, and they look cool on an exported image.
The REAL stats, with confidence intervals, are in the Analysis pane, aggregated from all shots of all groups of all targets.