Hmmm, interesting question Janie. I'd be interested to hear from MWs out there who regularly attend those kinds of births.
FWIW, I think (as has already been mentioned) you need to specify that you want to delay the clamping of the cord until it has finished pulsing and it's a good idea to breastfeed to assist with the contraction of the uterus.
Personally, I found the delivery of the placenta the second time was much quicker even without the shot (the first time I had the shot) but I'm not sure if that's common or not. I think the other thing the MW would have to judge is how much blood loss is normal and how much is excessive. They obviously have to know this anyway, but I think mine was really anxious about this and very worried about how much blood I was losing, whereas if I had've had the shot I wonder if she would've been so worried, KWIM?