Well, since you can move notes by mouse even when the clip position is locked, I think nudge and CAL should work just as well.
I usually nudge notes vertically (to transpose) and I don't know if nudging notes to left or right far away will extend the clip edge when the bug is fixed, but what I do know is that the "Apply Trimming" command works even when the clip position is locked (isn't this great? love it!).
I'm a heavy clip locker (since I don't want to accidentally/unconsciously move clips even a bit and it can happen so easily in Sonar since dragging the right half of the clip makes the clips' RIGHT edge snap to the grid lines), and not being able to run a CAL to change the note length from 16th to 8th for example (with a shortcut key) when the clip position is locked is a PITA.
So, #3 bug fix is quite important for me. :-)