Interesting rule. I think that would work well. Plenty of other rules also can work well.
Discussion
It worked for me because full day fasting (though no brainer) was too difficult for me - I was on full time work back then - and I had to cut down from 90 Kilos to 70 Kilos to make sure I am NOT put on diabetes pill for the rest of my life :-) .. going good after almost ten years hence ..