I want to draw a contrast between absorption and reflection. This has vague historical influences, but if it turns out that I am misreading Heidegger or misappropriating something, just focus on the concepts and not where they may have come from. By "absorption" I mean the modality of experience where one is "absorbed" in an activity. We typically speak of athletes and musicians being "absorbed" in their activities, unaware of "what" they are doing insofar as they are simply doing. In this sort of mode the boundary between subject and object seems blurry. By "reflection" I mean the modality of experience where one "steps back" and "regards" the very activity they are undertaking. Philosophy has typically been done in a reflective way--attempting to step back from the immediacy of experience in order to gain a third person perspective on things so that the structure, or logic, of experience can be made explicit.
Does Heidegger favor absorption to reflection? If so, I see his romanticization of absorption as problematic, and open to a relativization or complete degeneration of moral life. On Heidegger's account, we have gradually "forgotten" Being as such. We have forgotten how to be authentically attuned to the world, how to authentically be-IN-the-world. I characterize this as our movement from absorption to reflection. Nietzsche speaks of something similar, vis a vis the movement from master to slave morality. Or we could examine Richard Moran's recent classic, Authority and Estrangement. We are, indeed, increasingly estranged from our biological heritage- from our absorption in the practical concerns of surviving in nature. But this estrangement brings authority. As we are increasingly able to step back to reflect, we are increasingly moral. Following Levinas, we can see estrangement as the condition for the possibility of ethics. One's confrontation with oneself is the a priori condition for the ethical encounter with the other. When absorbed in playful, spontaneous, or violent activity, the other is but a feature of my world--and this is not the world. This is my world; my consciousness has absorbed it into the activity which consumes both self and world. In this mode, the other is subject to my activity and has no ethical standing.