From: "THE NGÖNDRO: Foundation Practices of Mahamudra" by Ringu Tulku, starting on p.87:
ibidThe attitude one encounters most frequently is that of people placing themselves under the domination of the guru, viewing their guru as their master and themselves as his or her slave. They do whatever the guru tells them to and, as they generally expect gurus to be quite unpredictable and strange, they are not surprised to be asked to do lots of funny thing, through which they are convinced they will progress and ultimately become like their guru. This is not a healthy attitude, but perhaps understandable!
I like the differentiation between the practice and the relationship. He does mention that a fully enlightened guru would be a special circumstance that is highly unlikely.Guru Yoga should be viewed as different from the actual guru/student relationship. We practice Guru Yoga as an ideal because it is a practice, an exercise. The guru/student relationship is something else. I don't mean that you should not have faith in your guru. It is good to have faith in our guru, but with an open mind and open eyes.
I'm not sure about Ringu Tulku's background. I've only seen him speak once. He spoke in English that's as good as mine. I like some of his books. But I'm pretty sure he's a well established Karma Kagyupa.If you are absolute sure that the guru is a completely enlightened being, that whatever he/she says is right, whatever he/she asks you to do is good for yourself and good for everybody, if you have no doubt about that, then of course you will fell devotion. It is natural. But otherwise, you may not. If you do not do something the guru tells you to, you do not break any vow. The Dalai Lama usually says that if our guru tells us to do something, and we thing it is not the right thing for us, we may tell him. I think that is right. There is no breach of samaya. I am not giving my own opinion; I am actually quoting from the texts.
He goes on about the nature of devotion, which we've touched on, but no the nature of faith. I can quote some more if people like it.