Brilliant wwaswas 😀
Seriously though, very easy to line the saddle up. I’ve got a couple of even odder shape ones, Yeti ASR-C and Scott Plasma, no problems at all. Both apparently done for aerodynamic reasons. It may help in a time trial on the Plasma at 25mph+ average, whether it makes much of a difference on the Yeti at 10mph average I don’t know, I suspect not.
Yeti one needs a special adapter to fit a work stand though.
It is to allow forwards/backwards flex for ride comfort while maintaining sideways rigidity under pedalling. The flat edge on the rear will be much less resistant to flexing than the rounded edges and should therefore allow the post to bend backwards to some degree when you hit a bump.