There are a lot of people commenting on things that they really don't know. How many here are real good at Fluid Dynamics and maybe also experimental evidence to pair with it?
Would you have come up with the positioning plan that they are using? I don't have enough experience with the Fluid Dynamics to have an educated guess. But note that FK had no one right behind her. Go watch NASCAR racing. I do think that her pacers did not help much and Faith will be much tighter and has likely been been practicing as have the pacers.
My guess is the shoes, clothes, pacing combine with Faith's grit and very smooth and steady running form to give her a shot, but I think 4:00 is optimistic and everything adds up to a 4:03 level. And not being even would add seconds to a 4:03 optimal time and how close she gets will depend on when she punts.
Also, the suit probably has monitors and they will track continually and compare with the training data. And her 4:07 was not paced for that time so it was less than optimal. And maybe she has gotten better.
Go Faith.