The ClutterAnimator support for parsing multiple properties should be verified in the conformance test suite. http://bugzilla.openedhand.com/show_bug.cgi?id=2003
The test_animator_properties unit is so small that declaring a mid-function block for two variables is not that clever.
The whole point of having the Animator class is that the developer can describe a complex animation using ClutterScript. Hence, ClutterAnimator should hook into the Script machinery and parse a specific description format for its keys.