What point of view does krakauer employ in his text? How does he address the tension between the objectivity of a biography his own sympathies for McCandless beginning in paragraph 5?

Paragraph 5
I I won't claim to be in impartial biographer. McCandless Strange Tales struck a personal note that made a dispassionate rendering of the tragedy impossible. Through most of the book, I have tried-and largely succeeded, I think-to minimize my authorical presence. But let the reader be warned: I interrupt McCandless's story woth fragments of a narrative drawn from my own youth. I do so in the hope that my experiences will throw some oblique light on the enigma of chris McCandless.