After listening to this a couple times, I realized that in Destiny, the only Guardians that were viewed negatively by the Vanguard were Toland and Osiris. Why? Because they "delved too deep into the Darkness." Toland dug into Hive arcana and, in my opinion now, set up his fireteam to die just so he could listen to Ir Yut and her Deathsong. We can say that he fell into the Darkness similar to how Dredgen Yor fell. All we know about Osiris is that he got too close to understanding the Vex and was exiled or left of his own accord. His current standing is unknown. Again, these are just my interpretations, but why would Osiris be kicked out for his research? His methods and ideas are too extreme is likely. I just wanted to put this out there, stir up some thought about the... [i]braver[/i] scholars in Vanguard history. BTW, I did not put Dredgen Yor in this because he wasn't researching our enemies, but was consumed by power.