Electoral reform - Hold out for the whole package, or settle for any little step and hope for more later?

Denmark in 1915 gives an example of a small step later extending:

1915 Denmark - Landsting (upper house) and Folketing (lower house) elected through PR.

Folketing members elected through Flexible District PR ("Rural-Urban PR") (mixture of single-member districts (FPTP), alongside MMDs in Copenhagen and Fredericksberg (list PR) with nation-wide top-up (list PR).

This system used just in 1918.

In 1920 PR extended across Denmark -- mixed member proportional, with some elected in multi-member districts using d'Hondt (none elected by FPTP), and some by overall top-up, using largest remainder and best-losers in local contests, allocated regionally.

Denmark's MMP system is still in use in 2026.

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But of course there is the counter-example of Alberta where STV was brought in just in some places and never was extended, before STV was dropped altogether.

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MMP was adopted in Germany (post-war in 1948) and New Zealand (1992), and has continued ever since.

Their use of single-member districts seemed to make adoption of PR easier but NZ has suffered some problems due to dis-proportionality of SMD results.

Germany has seen this so much that it has recently shifted to a requirement that a local victory must be confirmed by the party taking a certain percentage of votes overall.

But at least what problems there are has not meant the end of PR - in fact a majority of NZ voters voted to continue PR in a confirmatory referendum.

(Perhaps any PR system would have garnered that same support

- several times a majority of Irish voters have affirmed maintaining PR (STV) in that country.

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