How are you at perl scripting? OR shell scripting.  That's the way I
learned  a lot.  Write a script to scan for frozen tapes and report on
that.  Write a script to graph backup jobs by throughput speed, etc.
Write a script to verify the coverage of all your servers (There is a
coverage report but I wanted mine to know about snapshot filesystems,
etc)  Write a script to summarize failures and see which clients are
failing with which error codes more than x times in a single day...

By doing this you will ask questions like, where do I get this info?
Now you know where Netbackup stores this. Then you will become familiar
with how the info is being stored, logged, for how long, etc.  And of
course you will ask a lot of why questions, which once you have the
answer, you will understand a lot more about NetBackup.

But if the restore is serious enough/large enough, its still a good idea
to cross your fingers and pray...

Taylor