User blog comment:Nan the cowdog/Fanon's Head-Canons!/@comment-4353345-20130404042522

Somewhat related to Phineas and Ferb, I believe that whenever someone dies in one dimension, all their other-dimension selves die. Therefore, in the PnF movie, had Doofenshmirtz-2 been successful in feeding Phineas, Ferb, Candace, Perry, and Doofenhsmirtz to the Goozim, this would have also killed Doofenshmirtz-2. So, in hindsight, he should be lucky he failed.