Electron correlation lies at the heart of spin-polarization, the phenomenon that underlies ST inversion. Consequently, traditional TD-DFT methods for studying excited states miserably fail in describing singlet-triplet inversion, as was noted early on. To address ST-inversion, high-quality but computationally demanding methods are typically used, spanning from ADC(2), CC2, EOM-CCSD, Mukherjee's multireference coupled-cluster with noniterative triple excitations (Mk-MRCCSD(T)), CC3, Green's functions methods, 10 CIS(D), SA-CASSCF, and NEVPT2. We adopt a different strategy and conduct an extensive study of various triangular boron