Generally that is what they try to teach, but my point was that all you are really teaching them is that crying won't get them anything so they may not be tired, but are being "forced" to sleep when they don't want to and the side effect is that they stop crying.
I just don't think I see the point in creating extra work for myself by having to go in every 5 or 10 minutes, possibly for hours, when if I fed him to sleep or rocked him, IF he was tired he'd be asleep in 15 minutes, in bed and I could get on with what needed doing. Maybe I'm just lazy? LOL
I guess my other point was that we didn't have to "train" Alex to settle, this is just something he did on his own, and at night, if he's crying and doesn't want to be rocked and he's put in bed he's straight to sleep so for us, his crying can mean "put me to bed" instead of crying BECAUSE he's in bed if that makes any sense. The problem with those books is that they base it on the assumption that ALL babies are the same, and they're not. For us, it's alot easier to just go with what works, this goes for DS1 as well, and when they are ready they do it vs trying to "make" them do it when they don't want to.
So as I said, not got an issue with people who do it, just don't get WHY sometimes. At the end of the day we want to do what is best, but sometimes that is chucking out the book that says feed them to a schedule and "sleep train" them and just enjoy them and do what works for THEM, even if it's not what we'd choose. If it were up to me, DS2 would still be co-sleeping, and if not, he'd still be in our room but he refuses to co-sleep any longer and he actually sleeps better now that he is in his own room.
For anybody having issues with babies who don't sleep, hope it gets better soon.