I haven't seen the post in Sheldon's thread. All the lefties I personally know have learned to knit and crochet just the same as right handers do. Some that I've read about actually hold the hook or working needle in the left hand but most seem to be able to learn to use their right hand.
Cheating is an option. . . . Cheaters never win and winners never cheat, but smart knitters who want to retain an iota of sanity do, cheerfully. ~~Kory Stamper