I cant back it up as I dont have research to hand to do so. But Im pretty sure I could find some if I looked.
As anyone who has done a degree can attest, its not hard to write a paper saying black is white and find the relevant research and statistics to back that up.
In a way I do agree that episiotomies are done way too often but mainly by doctors doing instrumental deliveries, and I have seen some which are way worse than the tear would have been. Without looking closely at the studies stated, I would say with some confidence that they are taking episiotomies performed, rather than looking at who does them or for what reason, to come up with a conclusion.
Personal experience, while extremely important for the mother involved, is statistically insignificant in a huge group of delivering women, and so it is impossible to say what is or isn't necessary or right at the time.
After being a midwife for very long time and having delivered many thousands of babies, I know that if I have done an episiotomy, it was really necessary, and I also know that I have avoided many 3rd degree tears in the process, by guiding the damage away from the back passage. And I think this is the case for the majority of midwife births.
This cant be said for doctors doing an instrumental delivery though, as most involve some teaching and often a lot of episiotomies do extend to 3rd degrees in this situation. Obviously we cant ethically study whether these women would have had a 3rd degree anyway (due mainly to poor instrumental technique) or not.
Just glancing at these studies I notice that they are mostly (all?) American, and the overwhelming number of deliveries in US are done by doctors, most likely in lithotomy.
So how relevant to the UKs midwifery led care and delivery by midwives are these studies, (which are not just fresh off the press either)? Probably not very relevant I'd think.
LEILA- to try to answer your question a little bit, it really is hard to tell if you are going to tear worse than the epis. Probably not but hopefully you will trust the midwife caring for you enough to be guided by her at the time. Just talk to her about it when you go in in labour.
Sorry if this is a bit rambling - need to go to bed!