Also, I would need to see some data that an average person is going to be able to build enough muscle while losing body fat to add on an extra 1000 calories to their RMR. I'm not saying you're wrong, but I'm skeptical based on my knowledge. In fact, I would pretty much say "no way" unless one can stay anabolic and dedicated enough to build an above average amount of muscle.
Have a look at this paper using your favorite hub of science.
doi:10.1097/00075197-200103000-00011
https://journals.lww.com/co-clinicalnutrition/Abstract/2001/...
Based on this, a pound of muscle has a REE ~6 kCal per day.
So to get to the number you are suggesting, a person would have to put on ~166 lbs of muscle. That's not realistic most people, let alone those with plenty of fat to lose. It also takes a lot of time and money (calories = cash).
A person could work out that muscle and burn more calories, but there's a few problems with this as a fat loss approach. For one, you're going to need a lot of glucose to have a meaningful workout so you're already undermining fat utilization. Second, it takes time to build up that kind of muscle. It's both a short and long term time suck.
Let's say an average-sized person puts on that amount of muscle and utilizes all of it during a 60 minute body building workout:
6 METS x 3.5 x 75kg ÷ 200 x 60 mins = 472.5 calories
While that's not anything to sneeze at, it hardly matters anyway because muscles don't burn fat. At best you're just preventing the wrong kind of weight gain. To even get to that amount of muscle and keep it on you still have to eat at least enough calories to match that anyway. This is why working out requires more working out, otherwise energy will eventually be stored in the form of fat.
Or, they could literally just not eat that 500 calories and spare themselves the sisyphean task of relentlessly working out and not losing substantial fat mass.
Some resistance training is a good thing no matter what, but expecting muscle to be a weight loss aid doesn't make sense to me. At best, it's an adjunct to fat loss and should be done in intervals.
I'm absolutely open to having my mind blown on this. :)
The hormesis thing in particular is about introducing things in small amounts to get a beneficial response while limiting the harm that can be done in too much excess. Some things have no known hormetic level, lead being a prime example, but generally there's a level of tolerance to most things and beneficial pathways that are triggered by them. This is why when people say "only in moderation", they're only partway correct; moderation to many people usually means an amount of something that is less overtly harmful than average, but hormesis can mean taking in a very small amount of something infrequently depending on the substance and the intended effect. Small amounts of alcohol, for example, can have different benefits for decision making, creativity, and longevity, but the returns diminish rapidly if you either drink too much or consume any amount too often.
The other half of the equation, in relation to my point about adaptation being both positive and negative integers, is keeping the body on its toes, for lack of a better term. A lot of people hit a plateau on a diet because their body has reached a set point for the stress it endures. But occasionally switching up the input causes it to have to have to adjust to dealing with that new input at the current set point it has now reached. This is one reason why some people who have done keto long enough become shocked when they actually lose some weight on a carb binge, and they might even begin to question what they've been doing the whole time. Of course, what they were doing is still right for them if they are in good health because they become fat adapted, thus the body may need to do a certain amount of adjustment in order to start utilizing carbs efficiently again. This doesn't take long, however, since the body still fundamentally needs glucose, so if one were on primarily a keto diet then introducing carbs in brief periods may elicit beneficial responses in more ways than one. Not only can it mean actually dropping a few pounds here or there, but it can be just enough carbs that it improves sleep and allow for more meaningful workouts.
You saw a change in your results not only because you allow yourself a hormetic level of both rigor and relaxation, but you are in a way simulating the environment our ancestors developed in. We didn't develop to exist in equilibrium with our environment, as has been possible thanks to air-conditioning, modern insulation, and agriculture. Living in any particular state too long can mean getting too much of the adaptation we have for that state. Through strict diet and exercise, you are simulating a period of scarcity. When food was scarce or the environment was inhospitable, humans could only eat food that was calorie-thin while expending extra energy in order to solve that scarcity. By taking a few weeks off, which goes against the advice of many in the fitness industry, you are then simulating the time of good weather and good harvest. The body did all it needed to do during hard times, now it needs to shift mechanisms for the current environment. This fluctuation works because, if hard times go on too long, relying too heavily on our long-term energy stores can pose a threat to our survival; the solution is to reduce energy expenditure that occurs beyond BMR, limiting the amount of glycogen expended on excess movement, and focus that both glycogen and triglycerides on getting used to a harsh environment with no end in sight. In contrast, living like it's summer in California all year round, while having certain anabolic benefits and a good way to store up energy for the next period of scarcity, can result in negative health outcomes because our bodies are neither used to modern bounty nor are willing to pass up on an opportunity to store fat for the harsh winter that never comes.
So yes, hypothetically, there's a right amount of flux in exercise and relaxation that has a greater benefit than either of them alone.
At some point soon I need to research more of the evidence for or against this concept because I've become particularly enamored with the whole idea of hormesis as of late. It's biological in the strictest sense of the definition, but I've applied it to more aspects of my life than just diet and exercise. For instance, I rarely watch TV or engage in entertainment anymore, but I have also realized that just a little bit of either one is good for the mind and the soul. There are periods where I go through an "entertainment famine" where I simply don't watch/play any of it, and then I'll have a few weeks where I play a game or watch an old show I appreciate for just one hour in a day and no more. More so than "moderation", it enhances my appreciation without causing me to lose sight of the real world outside of the fantasy realm. Homo sapien sapiens, in contrast to our other Homo-genus relatives, are particularly imaginative. That imagination needs to be stimulated by other imaginations on occasion, but not too much.
People also just like to blow things out of proportion and go to extremes. Can't have any carbs or you'll be out of ketosis! Can't have that lemon juice in your water or you'll be thrown out of your fast! Yes, people do believe those things despite never having actually tested those theories themselves.
If there's one nearly universal "rule" I've learned about nutrition and weight loss (both of which I am obsessed with), it's that most approaches have a benefit at a hormetic level. Vegan diets, paleo, Mediterranean, keto, South Beach, potato famine, fasting, etc., all can work but all can also detract when pushed beyond a threshold. Hell, even a certain amount of sugar in one's diet is perfectly fine and has a benefit at its hormetic threshold.
The same can be said of exercise. Exercise has benefits, but it's often highly overrated. The primary benefits can be achieved at an incredibly low level. You don't need to run on a regular basis or lift heavy weights unless you enjoy it and find a benefit. To go beyond a certain point means compromising the longevity of your joints, providing negative feedback to your psychology rather than positive, overloading your CNS, and having elevated levels of cortisol.
In fact, for people trying to lose significant weight, anything beyond walking is likely to be a waste of time until they reach their target. Exercise is not an efficient way of burning calories compared to simply not eating those calories, burns more glycogen than fat most of the time (unless you really elevate your heart rate), and raises cortisol which is counter to burning body fat. Worse yet, many people go to the gym after work because they either need to lose weight or think that they've "just got to", but raising cortisol in the evening is usually counter to getting quality sleep or getting to sleep on time. If you don't get good sleep, you're detracting from getting to a better body fat percentage and staying there.