Hi ladies, just wanted to update everyone and kind of close off this thread.
As it happened, my second labour was a whirlwind. I woke up at 5:30am on the 12th with back pain but no contractions per se. Within half an hour they were there, and they were strong. I had my iPod loaded with the tracks and fully charged but I didn't touch it at all... at 6:30 I hauled my bleary-eyed DH out of bed, informed him that it was go-time and told him to start calling the midwife, doula and my mother. The doula arrived by about 7:30 and as soon as my mom arrived around 9 to watch DS we booted it to the hospital with the doula imploring me not to push (and, I later found out, following us closely in her car rather than heading straight to the hospital, just in case we decided to pull over!
). I was dilated 9cm on arrival. My second son was born just shy of 11am.
I don't know how much of the Hypnobabies courses I assimilated in that short time - I did end up only listening to the tracks before bed - but I do think they helped with the mental control part. Even though I knew what natural birth was like, I still had to talk myself through the fear of pain (at the first birth I had significant labial tears and the incursion of those hurt worse than anything else). I did have some tearing this time around, but far less and along an old scar line. I think the CDs also helped with the mental visualization of opening the birth canal and organizing the muscles to work effectively. While the birth certainly wasn't pain-free, it was quick and more importantly it was efficient. No pain meds whatsoever... but then my first birth had only nitrous (which did jack s--- besides distracting me).
So, the plan is to start listening to the CDs on the usual schedule next time around and see if I can combine speedy labour with innate pain control for a no-epi trifecta. Oh, and maybe produce a girl. LOL. 
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