Can you explain further your 30-40% thing? Cant see how you ended up with that number.

1. FIAT is just the trading pair. That's how markets work — you pair the asset with the most used asset for trading, which is fiat.

2. ? ? ?

"Chain-inflation": I can create my own version of the USD, but it wouldn't do crap with the economics of the USD. Same with with the bitcoin-forks.