While Pavarotti and his two sidekick tenors have been turning opera into a mass-appeal juggernaut, Bartoli has been trying to shrink a bloated genre.
Pavarotti and Bartoli do not get along at all. 
mnli hypothesis: Pavarotti and Bartoli do not get along at all.  premise: While Pavarotti and his two sidekick tenors have been turning opera into a mass-appeal juggernaut, Bartoli has been trying to shrink a bloated genre.