In a policy enforcement context, a PLE would be filled with misinformation. Like office grapevines and vicious rumor mills, information gleaned from outside or internal underground sources would be considered counterfeit, toxic and corrupting. Any PLE would undermine the transition from non-compliance to conformity. A PLE would be useless in this context where compliance training and policy enforcement meets the mandatory objectives.
In a problem solving context, a PLE could be used as part of a blended instructional design. Learners could subscribe to relevant feeds, tags and searches in order to deepen their understanding of the content being delivered in the classroom. The PLE could support the transition from mindless conformity to professional productivity. Abilities to problem solve, handle different use cases, and troubleshoot setbacks -- could be enhanced by calling upon outside, online resources. A PLE could function like outside reading, field study projects and practicums in conventional, offline classrooms.
In a person liberation context, a PLE could give the learner the independence to explore the knowledge domain informally and collaboratively. This context addresses the change in regarding each person: from a means to an end, as Stephen Downes and Wesley Fryer recently considered. Learners could take initiative to discover what they needed when they needed it with the support of their PLE. These experiences would prepare them for functioning as free agents, entrepreneurs or community builders. The PLE would bring diverse "live bodies" into their experience, transitioning them from controlled interactions to uncontrolled participation in diverse communities.
In a process nurturance context, a PLE would be in a continual state of flux. Instead of maintaining subscriptions to reliable resources, the PLE would be reconfigured every time there was a different question, unknown or mystery being explored. This fluidity could assist the transition from supporting "the personal access to resources" to supporting "the personal process of reflecting, internalizing and synthesizing contradictory inputs".
With these four contexts in mind, it possible to comprehend why PLE's has no appeal to most CLO's, appears to be going mainstream, and is getting so much buzz among us eLearning fanatics.