you obviously don't know anything about metabolism and starvation mode 
and you obviously don't know this simple principle
eating less = slowing metabolism
doing cardio = increasing metabolism
Again, this thread is about experience. I know what works for me and what does not, regardless of nutrition science, which is NOT an exact science (yet), because there are just too many interwoven and unknown factors. Scientific papers in nutrition science go against each other all the time.
Yes I know there are theories which say that (let's take 1h of daily) cardio (in addition to cardio from weight training and normal activities) significantly increases metabolism. In my experience it doesn't.
you can eat 500 calories a day and I bet you, you won't lose anyfat week after week, and all you'll lose will be muscle
The principles say nothing about the absolute ratio of fat loss vs. muscle loss at a certain rate of weight loss. They only say that the myths have no influence on it, as long as P1-P5 are met. Of course one would be stupid not to choose the appropriate amount of weekly weight loss acording to his caloric needs so that he can still meet P1-P5 and keep the aforementioned ratio as high as possible.
yes I eat 3,500 calories when I'm cutting
and I eat around 5,000 when I want to maintain
I eat 14,000 calories once in a while just for fun 
The total amount of calories is not important to the principles.
But as I said, if you really can eat twice the amount of calories (for mainenance resp. same rate of weight loss) by changing nothing else than adding 1h of cardio, you must be a genetic freak unheard of until now.