I don't know what the Byzantine generals problem is. Two stage commit is important because it has: 1) Predefined transaction id prior to final submission that

I don't know what the Byzantine generals problem is. Two stage commit is important because it has: 1) Predefined transaction id prior to final submission that allows you to validate the status, so if your request to commit gets 503'ed or you get a timeout you can reliably query to know if it was processed or not 2) Unlimited resubmissions of the final commit. It doesn't matter if I perform the final commit api request 1 time or 100 times, it will never cause a duplicated transaction to occur. So if I get a timeout or a 503 I can resubmit knowing that if my original commit request went in my new submit will be a no-op, and if my last commit request didn't get processed then this time it hopefully will be processed. This pattern isn't just a payments pattern thing either. This is heavily used in distributed systems where failures can occur. UPS' API used to use this as well so you could be sure that you don't pay for duplicate shipping labels or cause duplicate shippments.