I have tried to research this, but with no luck.
I get this error message…
http://www.lafayettehillremodelers.com .jpg is resized in HTML or CSS from 480x320 to 218x145. Serving a scaled image could save 37.0KiB (79% reduction).
It is the same for all of my projects. All of my projects are the suggested size. (700 x 467). I am thinking it is because there are actually 3 sizes for the same photo. One for the FP: Portfolio (which is the 218 x145 size), one for the archive projects page, and one for the project post.