Why Can Blocking Broken Chords Reveal the Harmonic Map?

When adults practise a broken-chord accompaniment, attention often settles on eight or sixteen successive notes: which finger moves first, where the hand crosses and how to keep the pattern even. Every note may be correct while the passage still feels directionless. Sometimes the problem is not finger control, but the fact that the player has not yet heard those notes as harmonic units.

One common practice method is to play the notes belonging to one harmony simultaneously as a block chord. This removes the flowing surface of the score, but immediately exposes the bass line, the moments when harmony changes and the points where the hand position must reorganise. If the player still cannot hear how one group leads to the next, the previous sense of familiarity may have come only from running the motions in sequence.

This is not a permanent rewriting of the music, and it cannot replace the original rhythm, articulation or pedalling. Blocking should be a brief diagnostic. After hearing one or two transitions clearly, return to the written texture and check whether the harmonic direction remains audible through the even figuration. If the hand is too small to hold every note comfortably, play the bass and outer voices, or divide the sonority into two parts. The goal is to understand relationships, not stretch the hand.

Movement research suggests that rapid piano sequences are organised into larger units, and that timing may become less stable at the boundaries between them. Those studies do not directly prove that blocking chords must work. The restrained conclusion is that when continuous motion conceals structure, temporarily changing how the material is presented can let the ear decide how the hand should group it.

https://pmc.ncbi.nlm.nih.gov/articles/PMC3728557/
https://pmc.ncbi.nlm.nih.gov/articles/PMC3499913/