This GitHub issue (specific to German):
gave me an idea.
Rules have a tendency to become outdated over the years, so we might end up suggesting exactly the wrong thing in a few cases someday. After every spelling reform, we should be able to go through the rules and modify the outdated ones.
rule element in XML could look like this in the future:
<rule id="x" name="y" timestamp="z">. The timestamp attribute should be mandatory. The existing rules could get the timestamp
12-31-2018, for example.
This might help with identifying outdated rules.