Just because people should not base their faith on the Shroud (though I think if a non-Christian can overcome his doubt through the Shroud and take the first step through the door because of it, that is not a bad thing) that does not make the Shroud un-important.
When it comes to establishing faith, it is unimportant. Believers don't need it, and unbelievers won't accept it. (Even if you could prove it came from the appropriate timeframe, unbelievers would then demand that you prove it belonged to Jesus.)
It is important and interesting for study. But ultimately, it is the Holy Spirit that draws us, not a shroud.