It's not a fantastic proxy, I agree, since the aggregation rule implicitly assumes linearity and it's almost certainly not. I think it's somewhat mitigated in p

It's not a fantastic proxy, I agree, since the aggregation rule implicitly assumes linearity and it's almost certainly not. I think it's somewhat mitigated in practice by the kind of small intersection between situations where it's strategically safe for a party to push bullet voting and where it's useful to do so being pretty constrained to elections where the top candidates are mostly acceptable to the same voters, though? I find it pretty unintuitive to construct an approval vote election scenario with a rational spoiler effect, and that's probably less big a deal than the vote weighting issues that crop up with multi-point score votes, but that's definitely something you can quibble over. The wider point imo is that compared to all forms of ranked choice voting, arbitrary-precision score voting is pretty obviously night-and-day superior (information-content-wise, at least), to which approval voting is a "close enough", at worst moderately inferior but at least theoretically equivalent, trade-off in favor of implementability.