I wouldn't consider it cheating to be playing a tenor guitar with DGBE tuning. Probably the most well known tenor guitarist in folk or any genre was Nick Reynolds of the Kingston Trio. I know for a fact that Nick played in standard guitar tuning because he not only personally told me, but upon viewing some of those old Capitol album covers it is pretty easy to see what chord configuration his left hand is making.

Nick Reynold's superb tenor playing, usually capo'd way up on the 5th or 7th fret was a very definitive sound that differentiated the Kingston Trio.