I totally agree -- I picked the latest version for each major version using the semver interpretation of the version numbers, which is not how PostgreSQL has traditionally done major version numbers (i.e., PG 8.2 and 8.1 are different major versions, but I interpreted the version numbers as if they were minor versions).
The main reason I did this was to reduce the number of versions I had to test, but I agree a more complete analysis would test each (true) major version.
The main reason I did this was to reduce the number of versions I had to test, but I agree a more complete analysis would test each (true) major version.