BFN is the breastfeeding network, SPB - another bf organisation.
The Peer Support model is very well established now and it has been shown that what is most helpful to mums is a listening ear from someone who isn't going to do what their MIL/HV/GF book does and leap in with 'oh, I had that, you need to do this...'. That is why there is such an emphasis on listening and information giving skills. As a PS you are a listening ear and a signposter. You don't need to know loads about bfing, but you do need to know how to work within your own limitations, how not to assume you know things, how to find things out, where to send mothers to for more in depth help.
You will be shown how to watch a bfeed to help a mum with latch, but there is no way that a trainer can include all the information about bfing there is to know in a short course. What she can do, though, is make sure you know not to advise women, but to listen to them, give them a chance to vent, or work out what they want to do, and then help them work out where to find the information and/or help they need.
The knowledge about bfing will come later on as you get more experienced as a PS and spend more time looking through The Breastfeeding Answer Book (for example), with a mother, or sitting with her while she spends time with the BFC you've helped her access.
The point is, if the trainer spent 7 weeks on inadequate bf information (because there's not enough time to fit it all in) and only 1 session on the listening and information-giving skills you need to make you an effective PS, then you could actually do more harm than good IYSWIM. As do many HVs who assume they know enough about BFing to advise women to do things without actually taking them time (primarily because they don't have the time, I accept!) to listen to the mother and find out what she actually wants to do.
Hope that helps explain it a little! I can see it's frustrating when you can't understand the motivation behind why you're being trained that way. Personally, I think she ought to be telling you why she's doing it that way, over and over again so you can really understand the point of it.
In addition, the reason the course seems wooly is because she probably wants to make sure that the course moves with what the trainees want and need, which will be different with every group.