hmmm I also don't think that drona humiliating karna part was there ...
but karna is essentially one of the most brilliant anti-heo - tragic-hero characters in world history... after knowing the truth about karna , yudhistira wanted to let go of the kingdom as he knew if destiny had its way , karna would be the ruler... then narada came to him to explain more about karna n his life, how he had restrained from killing each one of them except arjuna in the war even when he got the chance due to his oath to kunthi... n how actually , after bheeshma , it was karna who was the real heir to throne ... n even there was an instance where arjuna , after killing karna starts prasing himself , then krishna asks him to step down from his chariot n he too gets down n then krishna asks hanuman , who sat on the chariot in the form of a dwaj (flag) to leave the chariot ... the moment he left the chariot it exploded into smitterns ... then krishna explained to arjuna that if hanuman wasn't there his chariot wouln't have taken the blows of karna's sakthi... n even to the last moment shalya kept harassing n irritating karna to distract him from war... n there also goes a story that krishna actually offered karna kingdom n draupati herself , just before the war started (or after bheeshma feel, I am not sure) if he could leave duryodhana...
there is a national accademy winning book "karna' by Shivaji Sawant ... its brilliant ... covers the whole mahabharat n karna's life so beautifully