Definitely favorable conditions, as others have posted. Nadine Visser and Pia Poland each destroyed their lifetime bests at 100 hurdles in the same meet.
But I'm glad Laurent Meuwly was wise enough to set up this race for Bol. She needed a confidence boost and a race at fast pace. I don't think it was on her schedule until recently. After FBK Games last week she told the Dutch press her only remaining race prior to Paris would be London Diamond League.
The primary benefit of this race is that it shuts up the Sydney fans from abusing the line that Sydney is 2 seconds faster than Bol. They have desperately posted that line everywhere for 2 years. I wish my net worth could be rounded upward like Sydney McLaughlin fans view track and field.
There's also the possibility that this result could scare Bobby Kersee enough that he won't allow Sydney to run the anchor leg of the mixed relay. He has said Sydney would be available for that event. Bol and Klaver have much greater chance at gold in the mixed event than in their individual races. Obviously Klaver is underdog for any medal.