Eisenstein’s Montage

In Ralph Steiner’s H2O we see a whole short comprised of montage, exemplifying a few of Sergei Eisenstein’s definitions about the various types of same, but there are multiple types of usage that exist within the bounds of the film. There is the tonal montage which is clearly demonstrated in various point of the film with the nostalgic over lay of sound, though the images vary in length and content a general feeling of upbeat remembrance and contemplation seems to organize the bulk of the images. There is also the use of the metric montage which is comprised through the dissonant sounds which are mirrored by the various water scenes, in these moments cuts and clips are cued in nearly every way by their sonic counterpart. The film in its entirety has a somewhat rhythmic montage organization in that the length of clips is less important to the overall composition than the content of said clips. Eisenstein then moves into a discussion of the concept of over tonal montage, this is where the discussion becomes more abstract for me. What is this concept is as opposed to simply tonal montage and why Eisenstein thinks this is the future direction film should/will go in? Do you think it is the most effective use of montage?