It could be I suppose, becuase DD didtn'say that it was the failed curse that definately gave Harry parseltounge etc, just that it was his theory that it did...
Oh, but then I would assume that DD would know if Voldie was relatedt o harrry by blood... he knows everything else after all..
But maybe he's lying about it to protect Harry fromt he knoweldge...
Uhh, but then DD has never really lied to harry... he hasnt't old him stuff before, but never lied...
*uhhh, having big debate in my own head... maybe I should stop it now!!!

*
I still think no, harry is not related to Voldie by blood!
