Based on their responses they have ZeroClue on how to even perform a basic double-spend, instead they talk about unrelated things such as PoS and Sybil Attacks and [insert BS here].
 
Anyone can double-spend Bitcoin at will as we've recently witnessed and I was the person that informed the developers that it would occur due to their faulty signature validation code. The Bitcoin devs demonized me but in the end they realize my findings were accurate and the network split losing people hundreds of thousands of USD and forced zero confirmation transactions to be disabled on a wide scale. When I told them a hard-fork was required to fix this bug safely they said "we have more than hard forks at our disposal". This is the typical crypto-currency ego and if it continues the double-spend attacks will increase due to easier but more sophisticated attack vectors.

It is impossible to have safe zero confirmation transactions on any crypto-currency without it being part of the core protocol. This is what I have done and it resolves the problem for all crypto-currencies using a backwards compatible approach without the need to hard-fork.

I asked Nick Szabo aka Satoshi Nakamoto what he thought of my invention but he has failed to respond after many attempts.

I will not waste my time responding to nonsense. You have be given an opportunity, take it or leave it.

Thank you for your support.