I think someone has noticed by now, it just doesn't matter because no one cares. They would just be too lazy to try. It is much easier just to say that it is impossible, and then state the conservation of energy laws over and over to no end without any reason. You could destroy energy just by sending it down a half wave length wave guide. The energy will not go down it. If the worldine of an electromagnetic wave does not match up it just vanishes. It is a principle that is used in radar receivers. You could prevent all energy from going into a reciever that is coming directly out of a transmitter. This is the circuit used in radar. The energy comes out of the transimitter and then looks down the reciever, and says no wait that tunnel down there is only a half wave length, I am not going that way. So then what if that was the only way to go? It wouldn't be able to go anywhere. One of my instructors in radar theory said he use to work with the designers of military radar. They ran test to find out where the energy goes, and they couldn't find it. It will just be gone. They tried to tell scientist, but they just do not listen. It is as if the law of conservation has found it's way into the minds of scientist preventing a free energy device from being discovered because it brainwashes them.That would be last thing on my list after all other possible results were overruled. All that happens in a reflection is . . . reflection. In fact, reflection would be exceedingly difficult if other things had to be done in tandem.
A resonant cavity, a laser, an electronic phase inverter . . . there are some pretty widely used devices that go to great extremes to set up reflections - you think something would have been noticed by now if (theramin plays 50s alien invasion sound effects) something else was going on.
It is like the problem of saying that if there was a time traveler, then at the moment he traveled back into time, there would be more energy. The mass of the universe would increase by the amount the time traveler weighed. Electromagnetic energy interacts with itself through time. So then there can be an increase in energy at any particular moment. Particles traveling close to the speed of light do not experience time the same way we do. The worldlines in their frame of reference are contracted into the same moment, so then we can observe an increase in energy from the interactions that take place at other locations on their worldline. We see the particle as probably being at two different place, it sees itself as being at both of those places at once. So then altering its worldline then would alter the amount of energy it had at another time along the wordline.
A resonant cavity that is exactly a full wavelength in size of the electromagnetic energy inside of it should increase in energy over time, just like a resonant cavity that was a half wave length in size then have no energy inside of it. That is basically what is between the antena and the reciever of a radar. Then the circuits do not fry because they do not have energy from the transmitter being sent right into it, even though they use the same wave guide to the antenna.