I thought the consensus was that opening up the primaries outside of party insiders was a considerable force for increasing the idealogical and partisan candida

I thought the consensus was that opening up the primaries outside of party insiders was a considerable force for increasing the idealogical and partisan candidates. When the party insiders choose, then want moderate candidates who can appeal to more voters and win a general election. When the party "base" decides, they want partisan and idealogical candidates.