Why does WebPageTest show image compression results with suggestions that will have minimal impact on page load speed? Here are a few examples. Notice that some of the suggestions result in improvements of 0 k.
Compress Images: 81/100
44.6 KB total in images, target size = 36.5 KB - potential savings = 8.0 KB
WARNING - (9.8 KB, compressed = 5.8 KB - savings of 4.0 KB) - http://www.example.com/wp-content/uploads/2014/06/Activehours_iPhone-e1404099141905-150x150.jpg
WARNING - (5.8 KB, compressed = 4.5 KB - savings of 1.3 KB) - http://www.example.com/wp-content/uploads/2014/08/BaltaoPhoto_optimized_3-e1408486130319-150x150.jpg
WARNING - (4.6 KB, compressed = 3.4 KB - savings of 1.2 KB) - http://www.example.com/wp-content/uploads/2014/07/obopay-e1406855386176-150x150.jpg
WARNING - (6.3 KB, compressed = 5.6 KB - savings of 0.7 KB) - http://www.example.com/wp-content/uploads/2014/07/SanjivP-MC_optimized-e1406007406285-150x150.jpg
WARNING - (3.5 KB, compressed = 3.0 KB - savings of 0.5 KB) - http://www.example.com/wp-content/uploads/2009/05/Peek-66x66.jpg
WARNING - (3.2 KB, compressed = 2.9 KB - savings of 0.3 KB) - http://www.example.com/wp-content/uploads/2011/07/Technology-66x66.jpg
WARNING - (6.0 KB, compressed = 6.0 KB - savings of 0.0 KB) - http://www.example.com/wp-content/uploads/2014/07/Kamal_S_Qaudir_optimized-e1405575226757-150x150.jpg
WARNING - (5.3 KB, compressed = 5.3 KB - savings of 0.0 KB) - http://www.example.com/wp-content/uploads/2014/07/KidLight-e1405195581924-150x150.jpg
