I have absolutely no problems with Independent Midwives Enid - if I could I would be one!
The good thing about being an IM is that you can deliver care as you see fit. As a hospital midwife there are certain guidelines I must work within, otherwise I am breaching my employment.
As far as third stage goes, I am personally happy for any woman to have a waterbirth if she is anaemic as long as she is well.
The difficulty is that if a woman delivers with a Hb of 9g/dl, it is a risk to her if she has a postpartum haemorrhage. She does not have a lot of reserve to play with so if she bleeds, she might end up very anaemic needing a blood transfusion. In order to prevent haemorrhage, the third stage is managed with an oxytocic drug which makes the womb contract and the placenta deliver within 20 mins, usually within 10min.
Physiological third stage can last well over an hour or longer. However it can be all over in 10 mins too.
The way I would play it is to go for a physiological third stage but if there was any sign of heavy bleeding then convert to a managed third stage by giving injection and cutting cord.
Expat - we used to get women out the water for third stage because there was a theoretical risk of water embolism. This has never happened and there is no good reason to interrupt the third stage unnecessarily getting women out of water.
It is well worth getting the midwifery waterbirth guidelines I posted a link to earlier. There are lots of references in it.