Interesting everybody pointing out that BTC is traced through the public block chain - but what about BTC tumblers/mixers that are designed specifically to anon

Interesting everybody pointing out that BTC is traced through the public block chain - but what about BTC tumblers/mixers that are designed specifically to anonymize BTC transactions? I remember one Reddit thread where they chased some huge amount of BTC which were stolen and ended up losing them in one of these: https://www.reddit.com/r/SheepMarketplace/comments/1rvlft/i_just_chased_him_through_a_bitcoin_tumbler_and https://www.reddit.com/r/SheepMarketplace/comments/1rvlft/i_... As far as I know the thief got away with it.