Practical depends on how you end up using the knowledge right? For people into protocol development/exploitation it was a valuable course which taught many fun

Practical depends on how you end up using the knowledge right? For people into protocol development/exploitation it was a valuable course which taught many fundamentals of discovering cryptographic operational methods, flaws, procedures, and how to design or fix. The reason you always hear people say "never roll your own crypto" is because this is a difficult subject matter, but is necessary if you're trying to build a properly secure cryptographic schema.