You don't have any choice about this. I find this self congratularly attitude a bit thick. It isn't a decision not to work at home, it is the luck of the draw, nothing to do with "efficiency". If you have a lucky job in a lucky school, it is possible, If not, it is a choice between working the hours you are told to work or resigning.
I have worked in about 10 schools. Hours per week range from 65-over 100, which meant working straight through the night several times a week for about 5 years. Current job I get everything done being onsite 7.30-5.30 ( ie, the entire time the premises are open) previous job I did not get everything done being on site 5am -6pm - again, the entire time the premises were open.
No change in my efficiency, different jobs, different schools, different managers.
The best clue is to look for how many other staff are parents ( in the second school I mentioned there, no mothers at all on the staff) however, schools can change very fast, and a school which is reasonable to work in can become a school with a management of slave drivers with the appointment of one new member ( and yes, I do consider it slavery if you habitually have no opportunity to sleep or stop for a meal)
Having said that, it does work out well with child care in the school holidays. Half terms won't always match up with your child's schools, not will the start or end of holidays, but you are likely to get at least 4 weeks the same in the summer, and 1 week at easter and Christmas.
I did it as a single Mum. If you are in a city, where you can easily leave a school that has become unreasonable to move to another, it is doable. If you are in a small town with only 3 local schools within reach, much harder