I am of the belief that there can be 'too light' and this would show itself in windy conditions. I believe, and this may be my own preference, that a light, say 10lb airframe will not fly as well as an 11.5lb airframe in the wind - and by this I mean wind gusts will affect the 10lb plane more than the 11.5lb plane. Way back when.. (about 10 years ago) there was too light, and this was easy to tell as the airframe was not ridged - there was to much flex in it, between the wings and the stab. Now, with newer technology, I think this flex is gone (yet we see Beryll's being stiffened to prevent twist), but I could see how it might be a problem if you were trying to build a 8lb plane, 2M plane, just as an example. I suppose the leads to, if we raised the weight limit to 13lb, does the plane have an advantage over an 11lb plane in the wind? Perhaps it is in the thumbs?

sc