Regarding not fully focusing on the object:
"The importance of not focusing on the meditative object too intently should be emphasized here. You need to restrain your mind from wandering away from the meditation object, but you should also maintain a sense of relaxation. ... The function of the meditative object is to enhance your concentration. Simply be aware of the object, rather than grasping onto it or trying to focus on it too intently. An element of relaxation is extremely important here. You should not mistake the object of meditation for the function of meditation. The function of meditation is not to concentrate on a piece of wood or any other object."
(Traleg Kyabgon: Ocean of Certainty, p. 80)
"What is very important, the masters always advise, is not to fixate while practising the concentration of calm abiding. That's why they recommend you place only twenty five percent of the attention on mindfulness of the breath. But then, as you may have noticed, mindfulness alone is not enough. While you are supposed to be watching the breath, after a few minutes you may find yourself playing in a football match or starring in your own film. So another twenty five percent should be devoted to a continuous and watchful awareness, one that oversees and checks whether you are being mindful of the breath. The remaining fifty percent of your attention is left abiding, spaciously. Of course the exact percentages are not as important as the fact that all three of these elements-mindfulness, awareness and spaciousness are present."
(Sögyal Rinpoche: Natural Great Peace, p. 7)
"While teachers of the middle way, mind only, transcendent wisdom, mantra, and other schools may have their own assertions, the fulfillment of those intentions is the same. There is not a single thing that is not contained within mind."
(Gampopa to Düsum Khyenpa, in "The First Karmapa", KTD Pub, p254)
“If you recognize the world of appearance and existence as the mind, realize the mind itself as empty, and have no grasping at the superiority of your realizations — this is the ultimate view."
(Chegom Dzongpa, in "The Book of Kadam", Wisdom Pub, p609)