Storey, I do recall seeing SVC's 'list of regrets', IIRC including, amongst other things, the Jindarians, the Positron Flywheel, the Ion Cannon and the Temporal Elevator.
The Gatling was not on that list. I'd remember if it was.
The Gat has been in the SFU since 1980. SFB E 2.15 describes it...