Thanks for the detailed and very thoughtful response. Yes indeed Paypal does have instant payment. And digital currency payments have been going on over the Internet for a long time. Blockchain does introduce a slightly different paradigm and is potentially cheaper transfer than prior methods. But is not instant for current blockchains in production and that was what the patent was attempting to address. Yes indeed BOA do have a few patent applications in this space as well. I looked at a few in the past but none of them so far look like game changers either.
Regarding Ripple and Stellar, if you have all your nodes permissioned and trusted the Byzantine Generals problem becomes less likely to be a security issue. I mean which of the IBM nodes that currently make up most of Stellar's nodes will be attacking the network? But then you have a centralized solution. So its like there currently is a trade off matrix between scale, speed, decentralization, and high security where you cant get all 4 at once at this time in any current production blockchain.
I wouldn't lump Ripple and Stellar together. A lot has changed. Stellar is running on new code and algorithm. Unlike, Ripple, they designed the system to be fully responsive, but not at the expense of correctness. Stellar's new consensus protocol takes things to the next level with their Federated Byzantine Agreement approach. With this, each node chooses its own quorum slices. The slice selections and nodes are required to maintain a balance between liveness & safety. It's undeniably the 1st provably safe consensus mechanism with the four key properties (1)decentralization, (2) low latency, (3) flexible trust and (4) asymptotic security) working simultaneously. It's better than any mechanism including POW - POS - Tendermint - Byzantine Agreement. I am willing to bet we will see a major shift with many dapps moving over and utilizing the SCP. The possibilities are endless if it scales like it should. We shall see.