ORIGINAL: daven
It would have been more than a couple years ago, I believe you are thinking of Nick Maxwell, and that was 2001. Steven Baker may have won (Senior) with their conventional stabbed low wing, but that was more than 5 years ago also. The open class has been dominated by v-tailed aircraft since 2000'. Had some of the better pilots flown conventional tailed aircraft the results may have been different, but it was right about then that just about everyone converted to the V-tail and it took over as the standard in National competition.
Brain cells are unreliable, temporary fleeting things. 2001, 2006, close enough..
I figured it was some sort of combination of the current standard being flown by good pilots, and the actual benefits of that standard itself.
On this aircraft I'd be tempted to tell folks just to use what they know and prefer. Dunno what the actual difference is but it wouldn't be any kind of show-stopper.
MJD