Scrolling in the Timeline? Following the audio playback ...

For large scores it is useful to have the audio going while the score passes by. However, for locating particular features, such as a cymbal crash, the Timeline is sometimes more useful.

I tried this in MU4 recently, and wondered why the Timeline doesn't have a movable cursor which follows the audio playback.

Surely this would be useful to have. Is this perhaps difficult to implement?