Ermmmm.... I'm not sure I want to answer that question
But for me, I use it to hold that second weapon until I can use it. You can also put a shield there, but all a shield does is lets you block some attacks. If you have the fletchery skill, you could put a bow in there and start making arrows. Or even shoot bad guys.
But at this point, you don't have fletchery. You'll get double-strike far sooner.