For me a guru is one who removes the darkness of ignorance… ignorance of the self. A Guru is the one who has been able to remove darkness of self-ignorance and enabled you to attain self-knowledge. One should completely surrender oneself to the guru and await his grace.
I had read somewhere: the mother feeds her sleeping child at night, however the next day the child feels he/she has not eaten anything. Only the mother knows that the child drank the milk the previous night. Similarly, the Guru is aware of the disciple’s progress. It is great to question our teacher for a better explanation, but we should try and first understand what is being explained without bringing our two bit to the matter. I clearly understand from Guru Sutra that a Devotee evolves into a disciple not when he considers himself one, but when his Guru accepts him as such. One does not choose a Guru… it is the Guru who chooses you.
How does a disciple maximize learning from a Guru?
One should have an unshakeable faith in one’s Guru and completely surrender oneself to him. Surrendering is one of the best options for self-advancement. Never question your Guru. Never disobey him either. Another most important thing to maximize is your learning is to be disciplined. Discipline your thoughts, behaviour, actions and spiritual protocol.