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Sorry, but this has got to be one of the biggest urban myths in astronomy. As I read this, I take your argument to mean that using a larger aperture is more affected by seeing than a smaller one?
Large aperture is more likely affected by optics that are not at ambient than seeing itself. Cells of air movement are many kilometers across and would not have the type of effect suggested here. Nor will stopping down a scope make the seeing better. It might make the view better in an uncooled scope but not the seeing.
I use a 14" at ultra high resolutions and the difference between a naturally cooled telescope and one with active cooling is like chalk and cheese. You cannot ever get a naturally or fan cooled scope to ambient temperature. Anything above 0.5 degrees C will have an effect on the image quality or the way the image is presented. I have demonstrated this to many times over the years and the difference is staggering.
Imaging at the native focal length with an uncooled image will have less effect than at high resolutions. I have viewed Jupiter at very high resolutions in good seeing with an 18" telescope and seen detail visible in images. Anthony has too. Use active cooling on your scope Peter and you will see the difference.
Sorry if anyone takes offence. I am passionate about this topic.
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