Hmm, polite but i do find it curious how DAG can write such poorly informed nonsense at times when he appears to know the value of research etc in his own specialisms. Sure it's only a blog and we're all guilty of that to an extent but here it really is just parroting out the fptp 'party lines' about PR that largely only concern large closed list PR systems that neither of the major campaign groups are advocating. Ie basically strawmen.
Both the Electoral Reform Society and Make Votes Matter promote STV (as used in both parts of Ireland, Scottish locals and, historically, university seats in Westminster) or MMS (Scottish parliament, Welsh & London assemblies) as their favoured systems with a slight preference for the former. Both keep constituency links, both have by elections and one has reduced list influence, the other none.
He has a similarly bizarre take on brexit, being adamant he preferred leaving but endlessly critiques everything that's happened since and has only ever been incredibly vague about the sort of brexit he'd want, describing it as a close association agreement. I.e. just a different set of unicorns.