Linear Gamma RGB Color Space

[SomeGuyNamedDavid]

Blurring or blending between two colors tends to result in colors in the middle that are too dark. In Photoshop, there's a setting called "Blend RGB Colors Using Gamma" which solves this blending issue. In GIMP, I've heard some talk about a similar solution, but have not been able to find clear instructions on how to do it.

This video talks more specifically about what exactly the problem I'm looking to solve is. (The relevant bit starts at 2:17.)