This work provides a new perspective on the mechanism of intramolecular singlet fission in which destructive and constructive quantum interference (QI) plays an essential role. While graphical models to predict QI based on connectivity have been successful in single-molecule electronics, these models are not as obviously applied to light-induced processes involving exciton transport in donor-bridge-acceptor systems. Here, QI graphical models successfully describe multiexciton formation as a function of connectivity in a variety of acene bridges, which is effective in part due to the symmetric nature of the iSF chromophores. Moreover, we found that both bridge resonance contributions and structural distortion arising from steric interactions with the chromophores also impact triplet pair formation and the magnitude of QI effects. Understanding electronic structure contributions and QI to the fundamental principles of triplet pair evolution is important for optimizing the formation of entangled spin states, enhancing their utility in quantum information technologies.