Not really. This isn't an actual vulnerability of the network to double spending, it's just a wallet (or wallets) issuing multiple transactions for the same c

Not really. This isn't an actual vulnerability of the network to double spending, it's just a wallet (or wallets) issuing multiple transactions for the same coin (he may actually just mean the same address rather than the same coin, so that you don't come a cropper of the private key issue). This is possible in pretty much all cryptocurrencies, and their mechanisms for dealing with it (ie only honouring one of the transactions) is one for the core functions of any cryptocurrency.