Is Nick grading Dr. Langston?
No he is the assistant supervisor he is doing pretty much the samething that Greg had, just a different method (different people, different ways), he questions him and walks him through what he was trained to do. My guess is that part of it is grading, the rest is helpful teaching/learning.
The autopsy gross, and the 'fresh and minty' comment I didn't get
The toothpaste was a minty fresh flavor, so when Doc said "Minty" and Langston said "Fresh" that was what they were referring to, though at the time they may not have realized that it was toothpaste they were smelling.
As to my thoughts on the episode two separate and very different style cases I found refreshing it wasn't your classic way of doing things including solving them and or their outcome. What was thought to be a murder, pointed to a murder turned out to be an accident, not to mention the fact that Nick admitted the fact that the evidence was right it was the interreptation that wasn't (ie human infaliablity) to the point they had to review the case from the beginning.
The second case not your normal way to try and pin a murder on someone this though confusing and sometimes aggravating was pardon the term refreshing.
Overall this showed many sides in one episode the human element while interepting evidence, how the uniqueness of each case can lead in not just one direction and can hit a wall. I liked this episode, they used all that plus many of the techs. I did feel bad for Langston the poor guy just wanted to eat! As to the office deal, I think maybe that was part of the whole thing, Nick, Riley, and Greg are in one office, Catherine has her's, so why shouldn't Langston have one as well, otherwise just be mighty lonely in the break room. I love the fact that Langston liked his new office most would have seen the closet and gave a look like uh no thanks, he looked like a guy who just opened a shiney present at christmas.
As to Langston being on a lot I like that too were learning alot about what a newbie is going through, we forget sometimes that Greg learned a little more quickly because he was already apart of the lab so he watched, listened and learned. We had a shot to see a newbie on the job with Holly but they killed her off, so now is another shot at it and I am finding it fun to watch. ... I am giving this ep a 7 out of 10.