we read it and it worked amazingly well for my first daughter. (now 5). it basically enforces the idea of swadling. but there is a video you can watch too so if you don't have a lot of time, get the video on netflix or something.
ill say, this technique did NOT work for my second. but we figured out each baby has different needs. they were both good sleepers by 4 weeks.
my first HAD to be swaddled in order to calm down. she loved the vibrating bouncey seat and those classical baby videos seriously got her to stop crying on a dime.
my second daughter... nooooooo way. swaddling made her scream worse, she needed 'silky' blankeys, she HAD to have a pacifier, she hated bouncey seats and swings and couldn't care less about classical baby.