Hi All,
This is my first post to this list, so I will keep things brief. First of all, I love Inkscape, and this is the reason for the message.
My tests indicate that, when rendering, Inkscape implements anti-aliasing and transparency directly in a gamma-corrected color-space. Am I right? It is my opinion that these operations should instead be performed in a linear color-space. Although it is now probably too late to change the default behavior of transparency (given that the artists used gamma-corrected blends as reference while creating their content), it is not too late to modify the behavior of anti-aliasing. Also, perhaps a tag could be used on future files to identify that they were created under the assumption of linear-blends.
Jim Blinn has a very good article on the subject:
Jim Blinn, 2003 "A Ghost in a Snow Storm", Jim Blinn's Corner: Notation, Notation, Notation, Chapter 9, pages 133--146, Morgan Kaufmann
There, he explains the problems that arise from performing blends in a non-linear space, in better words than I ever could. At any rate, I'd be happy to give examples and to elaborate on the topic once I receive a message that reassures me I am posting on the correct alias.
Kind regards and thank you for such a great tool, Diego