20:4 with one big meal and snacks? Too extreme?

Hello, many years ago my first introduction to intermittent fasting was a friend that did something like 20:4 but in the 4 eat whatever they wanted. It worked but gained weight back as soon as she stopped ofc.She talked a lot about how there was science behind the fasting period and how it was difficult to over eat in such a small window which is why it worked. I feel like eating from 3 pm - 7 pm wont be terribly hard with the right mind set and eating nutritious whole foods, and some food for enjoyment. I want to start tomorrow by switching to black coffee and just push through until 3. I also went from a moderately physical job to a desk job last year which is mostly when I lost control of my weight. Advice? Warnings? Thank you in advance. via /r/intermittentfasting https://ift.tt/UVjCpR2 https://ift.tt/mY97Lco