Here's how the story goes.
Castagnetti was #14 out of 15 to pull papers
Nat breen was #15
Castagnetti also pulled for mayor.
Castagnetti, allegedly, was told he could only choose one - mayor or council.
Someone in the know told Castagnetti he could run two campaigns simultaneously
Castagnetti chose city council, which, along with Nat Breen pulling papers as candidate #15, both caused the primary.
Had Nat Breen not pulled, no primary
Had Castagnetti gone for mayor instead of council, no city council primary.
They both were responsible ...and I'm happy that there was a primary...because this 2019 election has played Simon and Garfunkel (The Sounds of Silence) so poorly that a primary was needed to wake up the sleeping masses.