As a reader, blank lines don't keep me from feeling jerked around when I am taken from one POV to another, not for my benefit, but to make things easy for an author to explain something to me. And all too often it's something I am intelligent enough to have figured out for myself if the author had SHOWN me rather than decided to TELL me.
Editors don't care how many times you change POV, as long as it is for the reader's benefit. Neither do I, whether I am reading a book or judging a contest entry, if the transition is smooth and enhances my reading experience I may not even notice it. If I do notice, it's usually because the change hurt my relationship with the story.
As a reader I get involved with the POV character. I care about him or her and their goal, and the inner and outer conflicts they deal with during the scene. Especially their Inner Conflict. So I want to stay with t hem until the scene ends, I don't want to be yanked away or pulled away or even blank-lined away into another character before that happens.
I know there are techniques like cutting where the reader is deliberatly yanked around to increase the level of suspense. And I know there are authors like Sherillyn Kenyon who are often sited as examples of why POV changes should be allowed. And the intimacy scenes where moving between the hero and heroine is almost a requirement. But those are special cases. (Yes, I love Sherillyn's work and use her as my own personal text book, analyzing her to figure out how she makes it work when so many other authors, myself included, can't. And I do see her as another of those special cases)
I would like to ask why writers (usually beginning writers) think they need to change POV inside a scene. A scene is a unit of conflict, best told from the POV of the character that has the most emotional conflict and not ending until that character's conflict is resolved (either things are made better or worse - and I admit I like it when they end up worse off than ever) At that point, a switch to anothe POV, often done in the sequel to the scene to set up the next scene, doesn't damage my reading experience.
For this reader, give me one POV until the conflict is the scene comes to a head. Let me stay with the character I care about and I'll finish the book and run out to search for your next one.