Libby could have easily got to the river during those 11 mins. But the point is, she doesn't have to had. Just because the screaming stopped doesn't have to mean she was in the river then. She had plenty of time to stumble there, getting more and more disorientated and upset.
@JosieJo I agree with you too. I find it strange that PRs behaviour is being super analysed but the fact that Libby presented in such a way as you describe is barely being considered.
I find it more believable that the state Libby was in could have got her into the river than the quite rapid escalation in PRs behaviour leading to murder. Even if it did, I find it completely unbelievable that he in the middle of all that had the presence of mind to act so quickly and efficiently that he managed to then dispose of her body without leaving a trace of either of them ever being in the park in a timeframe that the prosecution don't really want to bring attention to.
As I have said before, this is just my opinion and I still think PR is a piece of **** that should go to prison for a long time. I think he took her from safety and put her in a position that led to her death but if I had only heard the evidence that is in the public domain I could not say guilty to murder. Hopefully, the jury has heard much more and Libby's family will get some of the peace they deserve.