I think your Mum is right, routine is good. Babies and children thrive on routine.
Personally I'd bin that book - sorry
We introduced a bed time routine from 10/11 weeks, this time I intend to do it from around 8 weeks. By bed time routine I mean bathing baby, feeding them quietly and putting them to sleep in the moses basket awake. At that age, they're still going to wake up for a feed 2/3 hours later but that shouldn't stop you from introducing a bed time routine.
We kind of just fell into a routine, by their very nature all they want to do is feed, have a nappy change and then sleep! Gradually the time in between feeds and sleeps gets bigger as they get older. Routine doesn't have to mean baby goes to sleep at specific times, it will change day-day for some babies, others will go at roughly the same time. For us it has meant missing classes at times but I'd rather my baby got his sleep, one missed class now and again never hurt anybody.
The one bit of advice I would say is really important, put baby in the moses basket/cot awake so that they learn to get themselves off to sleep without being rocked etc.....They then learn to go through the various stages of sleep which is really important.
Our son is 26 months and he's thrived on routine. He goes to bed at 7.15 and sleeps for 11-13 hours.
Just follow your own instincts about what is right for you and your baby, you can't go wrong then.