When comparing two similar activities; the 'video' of the map will be too short.
Example;
moving time - 20 mins
elapsed time - 25 mins
So - during the ride a 5 mins break
The video will be 20 mins......, but it will show the 5min break. So - the last 5 mins of the ride will be missing - as the video is only 20mins instead of 25.