Just an observation, curious if this is correct?
Looking at the newly generated coins in block 447947
https://blockchain.info/tx/30a18539613de8e49ecb3fc63c94c5ba138caf791566df2b51b0f71dfe800c91All transaction fees show up as "Newly Generated Coins"
If someone wanted to "wash" The history of their coins, in combination with help from a large pool operator, said person could send 0.001 transaction with 100BTC transaction fee. Would that large of a transaction fee still show up as "Newly generated coins?"
Also, someone trying to do this would not want to do it all in one block, but with F2Pool or Antpool they could easily add 0.5 btc extra fees in their blocks and wash 100BTC/day.
The history of where those fees came from and how it was distributed would still be in the blockchain. But, on first glance thru coin tx history, the end point would appear to be newly generated coins, erasing previous coin history.