“Add RPC methods for creating shielded transactions offline“

seems interesting.

what are some advantages to shielded offline TX. think i have a good idea, but would like a pro’s explanation.

It would enable users to store their Sprout shielded funds more securely, by (for example) having their spending key on an airgapped computer.

This isn’t a catch-all of course, because there needs to be some data transfer between the online and offline nodes, and this could be compromised (e.g. bad USB drive). But the bar to doing so is higher than if the spending key is on an online computer. It can also be preferable in some instances to have a much smaller trust boundary around the spending key, e.g. by using a hardware wallet, but that cannot be done for the Sprout circuit (but will be possible for Sapling).