South Australia is on a really daft timezone

There’s a rather nice article about timezones and how wrong they can be, which shows clearly just how broken the South Australian timezone (+9:30) is. If you look at the beautiful map, you’ll notice that all of South Australia (and Northern Territory if it comes to that) is in red; that is, behind the timezone. At 15° of longitude per hour (360° in 24 hours), the +9:30 timezone would be centred at 142.5° E. South Australia extends from 129° E to 141° E (see wikipedia).

If you look closely at the map, you’ll see part of Indonesia (West Papua) which is on the +9:00 timezone. You can see that the white coloured section (the centre of the timezone, 135° E) is roughly in line with the centre of South Australia. Surely this would make more sense? All that broken software which assumes that timezone offsets from GMT are always a whole number of hours would just work!!

(I recently came across broken software which did in fact have non-integer timezones available. Well, sort of. They had a special case for India on +5:30, but that was all. ARRGGHH!).