There was some discussion in Dewars book "
To the End of the Solar System"[1] about the different cultures at the national labs related to the development of nuclear thermal rockets. Something about the Los Alamos guys being all about experimentation, and blowing radioactive material out of the tail of the rocket, until an Oak Ridge director was brought in and mandating more modelling of internal behavoir. I may have those labs mixed up, it's been a long time since I've read the book.
[1]http://books.google.com/books/about/To_the_End_of_the_Solar_...