The laws of physics cannot be repealed or ignored; piano key length
definitely and absolutely has an effect on manual playability.
Leverage of the key, as determined by its total length and the balance
point, has a marked effect on touch weight.  Since location of the
hammer and wippen assemblies is determined by the optimal strike point
of the hammer on the string and cannot be changed, a change in key
leverage will have effects that cannot be compensated for by relocation
of the other parts.

Larry Lobel
Virtuoso Piano Service
Petaluma, California 94952  USA