I find it hard to doubt that left-handed pianists will have a distinct advantage in trying to play the Opus 10 Number 12. I would advise against trying to stretch the left hand in the course of doing the arpeggios. Start by putting your third finger on the A-flat above middle C; the initial fingering for the left hand will be 3413231323132313231323141414143. Well begun is half done. Since this is the revolutionary etude (note that the melody in the treble clef at measures 27-28 is what the last notes of the Marseillaise would be, if done in B-flat major -- did James Huneker realize this? -- I don't think so), it seems fully in keeping with the spirit of the piece to make the piano howl out those first semiquavers in the left hand. When you get to measure 9, it's time to start avoiding trying to stretch the left hand too much. I recommend a fingering of 5143214323412341, for the left hand of that measure, as a model fingering for the rest of the piece. I think if one is going to do any Chopin etudes, this is a good one to start with; its technical demands do not reach the merciless level of Opus 25 Number 4. This is the first post I'm making to pianostreet and I'll be interested to see what reaction it gets!