"I'm sorry but that's utter bullshit"
No it's not. And it's true in case of illness as well as childbirth. For various reasons some people will tolerate things that other people are not prepared to tolerate. I was prepared to tolerate a large amount of unpleasantness in labour because, unlike many other people I know who don't think it's a big issue, I had a very strong aversion to my babies receiving pethidine or fentanyl (through an epidural).
"It is a matter of luck to some extent. You have little or no control over whether or not you have a breech baby, or shoulder distocia, or a sudden placental abruption, or any of the other complications that mean you need immediate medical attention otherwise either you or the baby might well die. Having the right aromatherapy oil or chanting the proper whalesongs or whatever may well make a non-problem labour and birth feel better, but 'mental attitude' will do fuck all for a medical emergency"
You know arguments like this make me really cross, because they're based on the false premise that there are people out there actually making a case that 'having the right aromatherapy oil' can make a difference to outcomes when it comes to something like shoulder dystocia or placental abruption. Actually - as you well know, nobody - nobody - would be or has been stupid enough to suggest anything of the sort. Why use an argument like this except to try to ridicule someone and wrongfoot them. It's like 'sheesh - these natural childbirth idiots - they think that all problems in childbirth can be resolved by chanting or having a positive attitude'. Well actually they don't, and it's insulting to suggest that they do.
In any case, the only significance of pain relief (which is what we were talking about) to cases such as you mentioned is that they make immediate c-section under regional anaesthesia possible, so a mum who had any of these complications wouldn't have to go under a G/A (not diminishing the importance of this).
Ironically though, having an epidural is the one thing that would make the complcations you mention above more of a problem - epidural anaesthesia immobilises mothers and makes SD more of a likelyhood, and if it happens, more difficult to resolve with simple manouvres. And the signs of placental abruption can be masked by epidural anaesthesia too.
And by the way - I had a fairly significant shoulder dystocia at my second birth, which was an unmedicated homebirth. One of the other reasons I didn't want an epidural for this birth is that I knew SD was more of a risk for me because I was carrying a large baby. The fact that the SD happened in a home environment and was resolved simply and quietly by two well trained midwives I think is part of the reason why I didn't come away from the birth traumatised. Almost all the people I know who've had this happen to them in hospital have had horrible experiences, with alarms going off, medics rushing into the room, big episiotomies and a general air of panic around the time of delivery.