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Now comes along the temperamental student, burning with ardour ardour
for the beauty of the music, longing to make the noble chords of some fine
melody speak out its message! What special pitfall lies ready to entrap his
zealous endeavors? Why, in his enthusiasm that the melody in both hands
should be properly brought out, he gets one hand playing after the other!

For Example is the Prelude in C Sharp minor.
by Sergei Rachmaninoff, Op. 3, No. 2. an
excerpt from the Prelude in C sharp minor of
Rachmaninoff, as written by the composer,
and (below) as often played by enthusiasts
with the right hand striking each note in the first two bars a fraction after
the left. In the third bar of the lower example the chords will be seen
arpeggioed instead of together, and again the right hand coming in after
the left in the last two chords. Another example is the Prelude in C Sharp
minor. by S. Rachmaninoff, Op. 3, No. 2.  

Only a fraction of a second after the left hand does the right hand strike,
but in that loss of simultaneousness of sound the whole grandeur after which
the performer is striving will be dispelled in the irritating effect of one part of
the harmony always reaching the ear at a slight interval after the other. This is
a most frequent failing amongst very musical people who enjoy tremendously
what they are playing; and especially does it occur with them in slow
movements, when they will arpeggio the chords between the two hands so
much that it sounds to me like drawling in speech, or even like stuttering.
These enthusiasts lose their sense of the symmetry of the sound in their
intense pleasure over its component parts, and it is hard that the very virtue
that lies in their love of the music can thus lead them into danger. 

Dragging the time, another tiresome error of judgment, proceeds generally
from the same cause of over-fervour. The player who suffers from this blemish
mostly owes it to lack of sense of proportion and taste, and to a certain want
artistic perception of the guiding line between true sentiment and
sentimentality!?