I love the tomm way of doing things, yes I know how to clean, however we have busy lives working and running around on a daily basis and I don't like cleaning on a weekend, so this method really works for me.
You do have to be tidy with it, your 15 minutes daily tasks and 30 minutes level 2 do not include tidying, it is literally just the tasks on the list.
I would say that when you first start it does probably take a bit longer than the 30 minutes, but you are not looking for perfection here, set your clock and stop when you're 30 minutes is up. It doesn't matter if you don't get it all done this week because you are hitting that room next week so pick up where you left off last week and it's job done. As you get more used to things you get faster at it.
You can always customise the list, so I don't clean my Windows every week, they just don't need it, they get done every month.
When you do your level one jobs, beds even small kids can fold their duvet in half, bathrooms I wipe the loo and sink every day, load of washing in the morning, tumble dryer after work fold and put away whilst tea is cooking. I don't always Hoover everyday, I use an old fashioned carpet sweeper and they honestly don't take longer than 15 minutes.
You do get faster with time and before you know it your house is suddenly clean and tidy most of the time. Doesn't matter if it all goes to hell during school holidays, just pick it back up once kids are back at school, but you do need to be tidy before you start!