Yak, in response to wind stability. I'm still going to hold my ground that a well trimmed light model will always handle wind ( and gusts ) better then the same model, poorly set up andcarrying an extra pound. The well set up model will always react less to any wind disturbance and when correction is needed, it will be a smaller input.

Your reference to sailplanes is interesting. Yes at times we will add weight to increase the wing loading of a sailplane. The reasons are completely different however. With the sailplane we are increasing the potential energy so we can convert it to a higher kinetic energy ( speed ). Usually at a slope or an F3B distance or speed task. Adding ballast because the wind has come up and we need the additional penitration to get from one thermal to the next is usually not going to happen. If the wind is blowing that much, the thermals are too weak and traveling downwind too fast for us to work them anyways. My 90 oz Synergy 91 does get bounced around just as much as a 60 oz Explorer even though it is heavier and I fly it faster.