I haven’t yet been able to cut and paste keyframes from one layer to another. It has to be possible, right? Select keyframe, command-c, navigate to new layer, command-v — should work, right?
Not for me. Not even if I add keyframes to the parameter first.
Clearly the developers were looking at After Effects when they made this puppy. Copying keyframes should be pretty intuitive for AE users (including the way new keyframes are added when you change a value on keyframed parameter, and being able to move keframes proportionately on the timeline – as in “option-select” keyframes, then drag the last keyframe back and forth.)