I don't think 1/4" is that far off, but, given a choice, I would tilt trailer nose down 1/4".
If nothing else, I feel certain you will at least pick up another 10 mpg by angling the nose of the trailer down as it pulled into the wind and the rear of the trailer will also act as a wind foil and help keep the tail of the trailer on the ground. Now the true advantage is when the wind is behind you and you present a larger and higher solid surface at the rear of the trailer to the wind and produce greater speed across the land minus the friction of the tires on the road. ;-)
Actually, I agree that I don't believe it will matter.
If behind a PU then lower as it needs more weight on the rear. If behind a wagon or SUV then higher as they do not need extra weight on the rear. Actually you have too much time on your hands to worry about 1/4" difference.
This post is my opinion (free advice). It is not intended to influence anyone's judgment nor do I advocate anyone do what I propose.
2010 Ford Expedition TV
2010 Outback 230RS Toybox, 5390# UVW, 6800# Loaded Not yet camped in Hawaii, 2 Canada Provinces, & 2 Territories I can't be lost because I don't care where this lovely road is going