That's really interesting, I would think you would be the most experienced person around to answer that question from the "pattern recognition" angle.Olaf:
That's a bit of a tough one. Might depend on just how you define" comfortable cruisers" But my guess would be a D/L over 140 and under 180, maybe as high as 200 if you want volume and stability. I think if you get the D/L under 130 you may have bulb provided stability but you still will not have a comfy ride. For the rig where you have some breeze I'd say nothing over 17.5 in a mast head rig and nothing over 18.50 for a frac rig.
There are a lot of variables but I think those numbers are relatively representative.
According to sailboatdata, the Adams 13 has a SA/D of 29 and Disp/Length of 96.
The Radford is lighter and has more sail, can't find published figures but it will be even more extreme.
A lot of folks have cruised a long way in the Adams ,including some close friends who don't have any issues with comfort, just note it is very tender upwind.
Do you think beam becomes a variable at this level? The Adams only has 10' beam.