What is it?
They are testing big blocks in another chain or simulator, or what?
this is a testnet for segwit. before a release to public or on the mainnet Core is testing all the improvements.
sure they are... we are testing bitcoinPure on skynet platform atm. this will allow us to send bitcoins to mars via our dark side of the moon mining node . at bitcoinPure we are always thinking ahead of the segwits and botnets.