this is from a talk with Karl Sanders of NILE(yea!!!!!!!!!!)
"well , on the plus side, there is plenty of NOTHING under the string -
where your fingers would normally slam into fretboard , there is now just air. Consequently, the note now has nothing to do with the string touching the fretboard , it is only making contact with the fret itself.
To my ears this yeilds a purer bell-like tone -
also , since your finger is no longer hell-bent on sqeezing the strings all the way into a hardwood fretboard,
you only need apply enough pressure to gently touch the string down to the fret. ( any more would push the note hopelessly sharp)
So you can actually relax your grip a little bit.
But this is a double edged sword -
since there is no appreciable functioning fretboard to stop you,
you can very easily play WAY out of tune -
and sound quite horrible. "