Is this a Nacra 6.0 or a Nacra Inter 20? Sounds like it's a 6.0 which had a little less volume in the bows than the Inter 20. I could right my Inter 20 alone ( at 190lbs.) as long as there was enough wind to get under the mast and help lift the sail up, say 8+ knots, but that was with a carbon mast. Don't know about the aluminum one.

Oh, and you can pitch pole just about anything if you try hard enough, but the 20 foot boats have a bit more resistance than the 16 foot 5.0, as they have the much longer bows.