Hello and welcome to BW. I hope you can find the support you need from the mums who are in the same boat as you.
1) I don't know of an index of acronyms. I still come across new acronyms myself. So I ask and learn. Please feel free to ask too, everyone will be more than glad to help you. To get you started BW = Baby Whisperer, lo = little one, OT= Overtired, UT= undertired, OS= Over Stimulated, DH= Dear Husband, DD= Dear Daughter, and DS= Dear Son. Can't think of anymore right now.
2) I have BWSAYP and it never gave me the impression that babies were put to sleep on their tummies. TBH I always patted her shoulder or tummy, but Tracy suggests to roll the los on their sides in order to pat their backs.
3)Agree with pp (previous poster).
4) Also agree with pp. I believe that the do not cave in part is to be persistent and do it at each sleep time. Shush/Pat is a tool that will teach your lo how to put himself to sleep. As you said, los don't know how to self settle, and shush/pat will teach them how to do that.
5) My book is on loan to a friend so can't refer to the sleep chart you mentioned. However at this age my lo did 3 naps of 1.5-2hrs each and a 45min catnap late afternoon. She also used to sleep much longer than 8hrs at night. So it all depends on the individual baby. They are all so very different.
Keep in mind that EASY is no quick fix. And it is not a recipe. It is just a guideline, a pattern to follow in order to make the day more predictable for your lo and for yourself too. So one baby will be able to stay 1.5hrs awake and sleep for 1.5hrs at 3 months, while another baby the same age might be able to stay awake 1.25hrs and sleep for longer, or even less. This site is great for tweaking the routines to adapt it to your lo.
HTH (Hope This Helps) and feel free to ask away.
xxx
charm