Should a composition be studied away from the piano?

There are four ways to study a composition:

1. On the piano with the music.
2. Away from the piano with the music.
3. On the piano without the music.
4. Away from the piano without the music

2 and 4 are mentally the most taxing and fatiguing ways, no doubt; but they also serve best to develop the memory and what we mean by "scope," which is a faculty of great importance.