I came across an interesting volume: THE DISORDER OF THINGS by John Dupre, Harvard. You might know it. While I have not at all mastered (even read) all of his arguments, it is clear that he takes the stance that science is not, and can not, "constitute, a single, unified project". This obviously goes against much mainstream thought (e.g. the usual reductionistic stance - behavior > brains > neurons > biochemistry > physics). A major goal is to probe assumptions involved in different stances.
I suspect there is a spectrum of "hard" (DNA type) and "soft" (motivational model) type "facts", some of which stand more firmly across subjective stances than others. Part of this is how we do our filling in when "facts" are scanty, or based upon potentially unrecognized assumptions.
This book is in a sense a "case study" approach as you suggest, but obviously a series of "case studies" filtered by a single author. Trying to ask how others (and we) ask questions is a praiseworthy if difficult goal. First hand experience (such as "what happens if I deliberately take different initial stances?") is a good one. It at least allows others to formulate their own judgement.
Part of the appeal of the "phenomenological' approach, as I understand it, is that we can easily put blinders on without even realizing their effects upon our DESCRIPTIONS. This then affects, fundamentally, the way we seek explanations.
I guess my interest is something simple like this: I assume that ALL behavior is the product (mix, etc.) of intrinsic and extrinsic events. Thus we respond differently to different situations (change external events), and respond differently at different times to the same situation (due to changes of internal state). IFF one buys that, then the distinction between "objective" and "subjective" in our study of external events has limits of its own. In the behavioral sciences, such as ME interpreting YOUR mood, this tangle is potentially powerful. Its less powerful when you and I agree in everyday life that this object before us is a rock, or stick.
So, maybe (maybe not) its possible to scale this balance between objective and subjective. Others can argue, with justification, that one can never ELIMINATE our interpretative processes, and in that sense cannot completely eliminate the subjective side of this dance. Others still can (and often have) said that we are only directly aware of the facts of our awareness, and so on.
I think I shall bail out of this one for a while, with hopes that others can join us with their views. Your comments were (are) helpful.