I have day time routines for my kids and even though I'm a SAHM I like having them, and my kids like them as well.
We went through a period though where DS's sleep was absolutely shocking - waking hourly all night long - this went on a for a few months and I can say with 100% certainty that I wouldn't have coped if I'd been working at the time as well. I barely coped as it was. I definitely think that being in full time work would make gentle methods a bit harder to persevere with - since they often take a while to work. When you're seriously sleep deprived the thought of waiting a week or two for something to work might as well be a decade lol.