Yes.. It is most essential.. Long time back at Uni of Toronto (Elec Engg Dept) we used to have seminars every week . In this seminar one graduate student would present a current paper of interest to the group with derivations of the equations and discussions would follow . It would be presented in a formal way with possible  additions and alternatives of solutions in close detail  with at that time stenciled copies. This  made possible good collection of group knowledge for future reference . Sometimes new small discoveries of every sort were  also presented for intense discussions.  in detail ...In this way the group knowledge was increased. All in all this is the way to build Grad insights and surf new knowledge. Today with " Peer Learning" . and communication of ideas in a group being of prime importance .. grad school can be a real load of  valuable fun.

Good Luck..

Cheers