There is precious little explanation in the article you cite on how this is actually implemented on the back-end.

Banking plumbing is notoriously harder than most folks realize, and I wouldn't be surprised if there wasn't very hard (and very small) limits to how big of an amount / how many TPS you can actually execute with this system.

I might be wrong, but I'd be surprised if you could move 10M pounds instantaneously with this.