It has to be, in order to allow the car to 'creep'. There is no torque convertor to allow for a transition from stopped to moving, so they only way to vary any speeds that low would be to slip the clutches, and that is not a good thing, so they put that extra low 1st gear in place. That part seems to work as intended. Little strange, but I bet the other car company's similar gearboxes are the same way (I have not driven any yet, but have been told BMW's version is very similar).
In this way, 1st gear is engaged, and the 1-3-5 clutch is fully engaged at idle speeds. If you pay attention, you can actually 'feel' it engage almost as soon as you take your foot of the brake. So it can creep at a low speed, like a conventional automatic, yet have that clutch totally engaged (no slippage) and not go too fast.