Consistency trumps extreme measures always. If you go to the gym 7 days a week, two times a day, that’s extreme right? But think about how much progress you’d actually make if you could only keep that up for two weeks vs how much progress you could make if you consistently were at the gym four times a week for two months instead of two weeks?
Can we drop to 1100 calories and see a big drop in weight? Sure. But how long can you sustain that for in order to actually see progress? If you can drop to that and not be consistent with it and constantly ruin a deficit on the weekends, then it has the ability to cancel out the extreme measures you took during the week to make progress. Play the long game and be consistent. It will pay off in the long run!