The goal of any tagging convention is to make categorization and searching as simple and intuitive as possible. My suggestion would be to avoid separating the current, numbered tags out into a distinct set for each syllabus year, as that would only create more complexity. We should expect that most users will be concerned with a single syllabus year only, and make it easy to find the specific problem within a set, even if it means we no longer have a single tag that applies to every problem in a set.
For example, pset1 can currently be used to tag questions about mario, hello/hello.c, a few shorts and newly introduced concepts like style50. But as should be obvious here, we have tags for each of these specific elements. I don't see any reason that we need to be able to categorize them all under one umbrella tag like pset1; in fact, I think we should actively discourage that sort of tagging because questions should be limited to separable topics/concepts in the first place.
So, my suggestion for a new convention would be:
- Remove all numbered "pset" tags and replace them with tags representing specific concepts or problems.
- If the specification for a problem changes so much that the answers to older questions in that tag would be misleading or wrong when applied to the newer problem specification, create version-specific tags for that problem only. This would be a separate discussion.
- Tag questions about specific shorts, walkthroughs or lectures with the appropriate tag, but not a "pset" tag, leaving it up to the asker to make clear in their question exactly which video they're referring to (if necessary).
- Avoid using tags like 2015; they're not useful as the only tag on the question, any benefit of following or browsing them would be de minimis and having version-specific tags would make them redundant.
Implementing this as a new convention would mean searching through the "pset" tags for potential orphans and questions that need additional tags. There are about 700 questions altogether in those tags. Manual retagging would take a while, and might not be feasible if we're flooded with new users in January when the next course cycle begins on edX, but given the absence of active moderation on this site it may be our only option.