I used to think that the GF routine was harsh (boot-camp -like), but after 6 weeks of struggle with my baby, I have tried the GF routine, and it worked!
My son was colicky, I was breastfeeding him for sometimes 2 hours at the time, he woke several times a night, and then fell asleap on by breast in a couple of minutes, I got mastitis, my son started loosing weight (that's after regaining his b'weight)...nightmare. Two weeks after putting my baby on the GF routine, he started to 'enjoy' the routine, was smiling more, looked ever more contented and sleapt through the night from 10pm until 7 am. Then, from the time he was just over 3 months old, he started sleeping through the night from about 8pm til 7am. Now, he is 11 months old, he is in creche, and he sleeps 12 and a half hours at night, he eats well, and an is absolute delight to have around.
Try the book, and I hope it will work for you as well as it has worked for us.