Please read what I have to say.
This is not a QQ thread. This is not even a suggestion, but moreso a debate I open up to the forumgoers who I yield to as better understanding healing.
I noticed that resto shaman's Earth Shield is no longer dispellable. This got me thinking, "If you cant dispel charges from an earth shield, then why should you be able to dispel PWS?"
I could be out of date on this one, but I remember a shamans ES contributing a large part of their healing. Similarly, a PWS provides (traditionally) a significant amount of a disc priests "healing." But I have always found it extremely frustrating to throw up a shield only to have it immediately purged/dispelled and needing to wait before putting up another.
So I ask, if there is justification in making ES undispellable, is there justification in making PWS dispellable?
tl;dr: NO. Go back and read it.