Deep Follow-up for Gravitational-wave Inference: A Case Study with GW151226

New analyses of gravitational wave events raise questions about the nature some events. For example, LIGO--Virgo--KAGRA initially determined GW151226 to be a merger with mass-ratio $q\approx0.5$ and effective inspiral spin $\chi_{\text{eff}}\approx 0.2$. However, recent works offer an alternative picture: is lower-mass-ratio event $q \approx 0.3$ slightly higher 0.3$. This discrepancy has been challenging resolve as wide range differences are employed for each analysis. work introduces ``deep follow-up'' framework efficiently compute posterior odds between two different peaks in parameter space. In doing so, we aim help disputes true gravitational-wave associated conflicting astrophysical interpretations. Our proposal not replacement standard inference techniques; instead, our method provides diagnostic tool understand discrepancies results. We demonstrate this by studying three {$q$-$\chi_{\text{eff}}$} proposed GW151226. find $(q\sim0.5, \chi_{\text{eff}}\sim0.2)$ interpretation only preferred over $(q\sim0.3, \chi_{\text{eff}}\sim0.3)$ hypothesis $\sim1.7\pm0.4$, suggesting that neither can ruled out. discuss strategies produce more reliable estimation studies astronomy.