Do i personally think that the Shroud is truly the burial cloth of Jesus? No. Have I rejected the possibility that it truly is? No.
A concrete, irrefutable answer to the question of its authenticity or fraud is not possible at this time and may never be.
A few years ago, four postage size samples were taken from the shroud for scientific examination. These samples were taken from areas which experienced fire damage in the 13-14th century. Seems the carbon dating would be invalid if this is the case.
A very recent book on this topic adddresses the issue of "bioplastic deposits".
When carbon dating any purely organic material like the cloth of the shroud, one has to consider the presence of a layer of organic debris called "bioplastic" which is deposited on the surface of any such material of any great age by microorganisms which have been living on its surface for many years. These microorganisms incorporate more recent carbon in surface deposits on the material as they live and die. One would assume that the older the material, the greater the impact of such deposits.
The radiocarbon testing must be limited to the actual original material. Unless the bioplastic is stripped away prior to conducting the carbon 14 test, the test material is contaminated with more recent carbon deposits, giving an inaccurate, more recent dating for the artifact than it really merits. The carbon 14 dating on the shroud material was done prior to the knowledge of the existence of this "bioplastic" and hence gave a flawed result. The test should be repeated, correcting for this factor.
Based on many other independent factors - the weave of the material - the unknown nature of the manner in which the image was formed - the inexplainable accuracy of certain anatomical and forensic features - the presence of pollen granules from plants restricted to the Holy Land - the supposed history of the Shroud itself - etc, leads me to conculde that such a test, if performed, would vallidate the fact that this artifact is, indeed, what it is purported to be - the burial shroud of Jesus of Nazareth.