Bleak House by Charles Dickens

I usually tell students that if they're going to switch between first and third person in a story or a novel they ought to have a reason for doing so (form and function, rather than form over function) beyond that they want to or they need to. But Charles Dickens manages to switch between first and third in his funny, depressing, wonderfully large and long novel, without bugging me at all. Now the question is, is this because he is Charles Dickens and through long-accepted classic-status above reproach; or because I am wrong and students should switch point-of-view willy-nilly and all they want; or for some other reason. I dunno. I think it's number three. Each point of view section is so long (as opposed to say a short story or even a two to three hundred page novel) that it's never jarring to switch and I feel satisfied by each section before I'm forced to leave it. And maybe a little bit of number one, and a little bit of number two (it is possible to get to hung up on rules and repeat them on near-automatic from semester to semester--though for the record I resist automatic as much as I consciously can).