"According to a tradition—and, be it said, an erroneous one—Chopin’s playing was like that of one dreaming rather than awake—scarcely audible in its coninual pianissiomos and una cordoas, with feebly developed technique and quite lacking in confidence, or at least indistinct, and distorted out of all rhythmic form by an incessant tempo rubato! The effect of these notions could not be otherwise than very prejudicial to the interpretation of his works, even by the most able artists—in their very striving after truthfulness; besides, they are easily accounted for."
January 1, 1970
https://en.wikiquote.org/wiki/Fr%C3%A9d%C3%A9ric_Chopin