Reproduction steps:
1) Load the UnstableBundles project
2) Immediately Exit Unity Editor (these two steps are important because it ensures that the Library folder is up to date)
3) Load the UnstableBundles project again
4) In the project tree, click on "MotionBlur1" (NB: this step is important)
5) In the project tree, click on "VignetteMaterial" and change 'ZVenus' value
6) From the File menu click Save Project
7) View Assets\Materials\VignetteMaterial.mat in a text editor and notice that '_CyanTex' appears before '_WhiteTex'
8) Close Unity Editor and reopen it with UnstableBundles again
9) In the project tree click on "VignetteMaterial 1" and change 'Carrot' value
10) In the project tree click on "VignetteMaterial" and change 'ZVenus' value
11) From the File menu click Save Project
12) View Assets\Materials\VignetteMaterial.mat in a text editor and notice that '_WhiteTex' appears before '_CyanTex'