I knew about it long before I got to see the episode (somebody spoiled it in one of the magazines). It was fitting that the end credits were absolutely silent, showing Adric's broken Badge of Mathematical Excellence, and it annoyed me greatly that during the 50th anniversary marathon (Earthshock was the episode chosen to represent the Davison era), they used the same bright, spangly music at the end as for all the other episodes. Adric was a misfit no matter where he was. He was an outsider among his peers on his home planet - too smart and serious to hang around with his brother and his friends, and too young to be accepted as an equal among the adults. No sooner had he earned some respect from his brother, then his brother was killed. In the TARDIS it was a similar story - he was too-whatever (smart, serious, moody, etc.) to be completely accepted by the Doctor and Tegan. Nyssa was the only one who liked him for himself, and that was largely due to their becoming friends on Traken. Yes, Adric was somewhat selfish and self-centered. He'd grown up being constantly praised for how smart he was, and he naturally assumed he was smarter than almost anyone except the Doctor (Fourth) and Romana. I think he redeemed himself at the end, and came full circle () in the scene where he's facing his death and clutching the belt that used to be his brother's.