This reminds me of the controversy and eventual abandonment of leap seconds. Leap seconds were invented over half a century ago and always had clear, well-defined rules governing how they were implemented and when they should occur. Despite this, they were almost universally cited as a source of paralyzing confusion, even by experts, and even though far harder problems are solved every day by both software and human decision-makers. In the end it was decided to just do away with them¹ and let the clock fall arbitrarily far out of step with the planet. “Names in tzdb can be abbreviated, or not” may be clearly defined and obvious to all (or maybe not so obvious), but if implementers decide not to read the spec and just go with whatever today’s data file has, their code will break when something different happens, just like a minute that lasts 61 seconds. They will declare the new data to be broken and demand that it be fixed to match the implementations, not the other way around. That is what is happening today. -- Doug Ewell, CC, ALB | Lakewood, CO, US | ewellic.org ¹ You don’t honestly believe that tale about declaring a “leap minute” or “leap hour” a hundred or so years from now, do you?