Re: Is any crypto truly scalable to a global scale? BTC, ETH, IOTA, DCR, PIVX...?
I think you have no clue what the coordinator does. It does not create TX, does no POW, and does not confirm TX. It decides the growth direction of the DAG.
Please Coordinator expert, enlighten the rest of us what would the effects be on the IOTA network if the Coordinators network-cable was tripped over and disconnected? 
Its private-keys stolen?