> In that case I've misunderstood. If the simulations are to be at 0.2", and the SDSS PSF is imaged at 0.396" resolution, then if we wanted to use it and not assume that it was actually imaged at 0.2" then we would need to deconvolve for the 0.396" Pixel and reconvolve at 0.2", wouldn't we?
> 

No you've not misunderstood at all.

I think we're addressing slightly different points here.  In the line that you originally commented on, I was trying to simply say "This is meant to be an image of a atmos + optics PSF that has also been convolved with a pixel.  Hence there's no need to convolve it with a pixel."  That was *all* the information I was trying to convey.  I was not trying to address the additional subtleties that come with lying to GalSim about a scale vs. using it to make sims at 0.2" scale without lying about scales.   I realize that your suggested text was meant to cover both the information I originally gave plus clarify this additional point, however I found your suggested text to be a confusing way to deal with those two points.  I will think a little more about how to make this clear.