ok i normaly stay out of these however i read over the thread and the reason i can see that trent went ahead with the tune is for the fact he thought the shavings were from the camshaft/topend oil problem and didnt expect it to be a bottomend problem aswell
my reason for saying that is you've shown up... he's fixed the top end problem.. sent you away for a week, you've come back and he's checked the topend is all good so he's assumed that was the end of the problem which im sure any good mechanic would have done and he's started to tune the car and problem has occured and he's pulled it off the dyno again..
as for people saying he's saved your engine, well in a way he has.. you still have a crank that can more than likely be reused allthough it is fairly common for SR cranks to be cracked upon removal of even a good engine, your block is reusable and most likely your rods can be reused aswell.
hope that clears things up a little bit for you as thats the way it has come across as whats happened to me.