From a conventional wisdom standpoint it's baloney. But if you go completely without food you will eventually starve.
If there were studies concluding reducing calories led to weight gain then Colpo (a diet guru) would have paid you 20 grand for showing it to him. Corpses do not eat. They may bloat, but they steadily lose weight. So do long term fasters. I lost 50 pounds fasting one month. 22 days into the fast the weight loss accelerated. My results are not uncommon. You can reduce thermogenic metabolism with less food. That's a big duh, because thermogenic metabolism primarily digests food. Going with less causes less digestion but the calorie deficit grows with less food as does weight loss. Some eaters hit nutrient or hormonal balances that require replenishment to lose weight faster, thus the results of some some refeeds and higher caloric losses.
That's how I currently understand things.