I don't think Poulter is in the same boat as Karsta. I think Poulter was given her shot to prove/show she's the #1. Im pretty sure she had more sets than Carlini at WC19. But in the end, I don't think we'll have a #1. Neither of them have established themselves as Glass or Berg did.
Of course not. One is a tryout for the number 1 spot like you said and the other is for a continued stint with the NT. She played well enough to stay only she's futher down in the depth chart than when she first started.
Off topic: Does anyone know where Jacqueline Quade is?