No WL E ticket holders will enter a reserved coach as the rule is clear that their ticket will get cancelled on charting if it remained in WL status.
The passenger who are in WL after charting for PRS tickets will always tend to travel in reserved coaches as they think that why should i travel in unreserved coach by paying for reserved travelling. It is justified up to an extent. But if the PRS WL ticket get auto cancelled upon charting and refund is made easy, he will take an unreserved ticket with almost half the charge and travel in UR without any hesitation, or he will find any other mode of transportation as per his needs.