Sharath said "new asana new pain" last week in the conference here in Mysore. Anyone who practises Ashatanga yoga can probably relate to this.   I think practising some "old" asanas with a new approach can also create pain (both physical and emotional)... In my experience, if we stick with it and trust in the process, we can overcome some of of this pain (both real and imagined). He also said he took two years with one pose. I would love to know what pose that was, but I am not quite brave enough to ask. :-)