Amber is what Mage the Ascension turned into, really. Both games rely completely on the GM's interpretation of the world and it's 'reality'. I remember a quote from somewhere, I think it was tongue in cheek, that if a game doesn't have rules for falling damage, it's not a real RPG. There are zero benchmarks in doing activities other than conflicts with each other or the 'Elder' Amberites, which include several different versions of each of them, because not even Zelazny knew which one was the 'right' version, in fact, the book even claims it on page 121 that 'Zelazny doesn't say', that they don't know what about the setting is correct or not. The entire GM's section is all about 'what ifs' or 'maybes?'
It's all up to the GM to decide everything. It's a Mother May I to the extreme, even the 'Good Stuff'/'Bad Stuff', which is nothing more than supposed luck, is completely up to the whims of the GM. Hope he likes you, otherwise, he'll screw you. The entire game is based around inter-player conflict too.
Pundy, I'm going to call you out, after rereading my copy of Amber. You rail a lot about 'Storygamers' and 'Storygaming', and yet, this favourite game of yours is THE Storygame of the 90's.
In several points in the Amber core book, it speaks to making character stories, page 122 has 'Story Composition'. In the combat section it has a small bit on Combat as Story Telling, page 81. The entire book is a manual on how to do a Storygame as per your personal definition.
You cannot justify this, you'll no doubt try, but damn, this is a 'Story Game' as you justify your hatred.