Why the hell do I do it? Why scale a mountain that promises agony and infinite gut-wrenching possibilities? And why lace up my hiking shoes, carry a hefty backpack, and drag myself up a behemoth like Mount Amuyao?  Here’s the deal: Every ruthless, giant mountain I’ve faced serves a buffet of above-average pain and uneasy moments.  I’ve dealt with twisted ankles, aching knees, cuts, bruises, cramps, dehydration, and blisters that look like props from a horror movie.  Yet, I push on and invite all the agony.  Why keep pushing through the grimacing and wincing?  Am I a masochist? Why do hikers like me willingly sign up for a world of…