I've read TMM and I think the basic concepts are good, but I disagree with not using or having credit at all. I mean, sometimes you need credit for an emergency. Not like an I can't affod it emergency, but like an I can't currently access the amount of cash I need emergency.
For example, my dgo ruptured a disc in her back, and we wound up at the vet ER at 2am, Cost of surgery $3000 must be paid before they will do anything. I don't carry 3k in cash on me, the bank isn't open at 2 am, and I don't keep that quantity of cash in checking, so my debit card is out. I put it on my credit card. Paid it off when the bill came, and I had taken the money out of savings, but things come up where you need to pay and can't access the quanity of cash you need immediatly. Just something to think about.