There is no "Merge Clips" option when I select and right-click segments in the Expression timeline. This is an option for Motion segments and I'm surprised that this feature seems to be missing for Expression clips. Might I be going about it the wrong way?   

This raises another issue, which is that if I have two Expression segments on top of each other, I can't easily edit the keyframes in the hidden bottom segment. Is the only solution to move the top segment out of the way temporarily, adjust the keyframes on the bottom segment, and then move the top segment back? That seems very clunky and inaccurate.

Thanks!