I have heard the curve ball theory too. And it was right for me. First 10 hours from first contraction to birth. Second baby was 3 hours from first contraction to birth and born only 20 minutes after arriving at hospital. So they were all freaked out that the third would be quicker. I went in after about 2 hours of active labour at home with contractions 3-4 minutes apart. But she wasn't born for another 5.5 hours of painful, intense labour. I had an anterior cervical lip and no urge to push until 10 minutes before she was born. She also had shoulder dystocia (4.9kgs!) and so no wonder it was a hard labour. All three I didn't have any drugs for pain relief.

You can totally do it. Get a team of people around you who know how awesome you are and get a good known midwife. My 3rd midwife was the worst and possibly contributed to it being the worst labour.