Only in one source - GC - stretto is notated with dashes that extend over to bars 643-644, so an abrupt three times accelerated pendular ocatves is either retained in a tightened tempo or enhanced by a progressive stringendo (in musical practice the terms are used interchangeably, even though they have opposite meanings when looked upon by linguists). Such interpretation contradicts both the musical logic and possibilities of technical performance. Therefore, taking into account that the copyist may have made a mistake while noatating the extention of stretto, we propose to end it in b. 642. This will allow for a smooth transition between gradually accelerated minims in bars 637-642 and crotchets in bars 643-644, played in a normal tempo (Tempo I) or slightly accelerated.
Such a proposal is neither contradicted by EE nor by GE, where the scope of the marking is not given. In FE there is no stretto at all, probably as a result of less diligence in Chopin's creation of the alleged base for FE, i.e. [A2].
Compare the passage in the sources »
category imprint: Interpretations within context; Differences between sources
issues: Inaccuracies in GC
notation: Verbal indications