One of the things that seems to confuse a lot of new users of FCPX is the connections between clips.
And to be honest they can be a bit fucking irritating sometimes. However, thanks to a comment on this blog by gyula hegedűs I have discovered that you can actually move clips about independantly of connections.
Simply hold down ` and you can move clips on the storyline without moving any connected clips. Genius. Thanks gyula hegedűs.