I would say if you're using a spinnerbait don't use a leader, you will catch more fish and I have NEVER had a pike bite one off. I would say if you plan on using a jig, live bait, or smaller lures definately use a leader!
Wouldn't steel or titanium be thinner and more supple than 30# plastic line?
i have yet to see evidence of pike being shy because of a leader, even in winter with 50 lb black line and a 80 lb leader we have no problem catching many large pike, something tells me even 80 lb floro. is not as tough as 80 lb titanium wire.