well, it is okay to not believe what is in the rules. In Hattrick it shows that the teamleader, being in the rules for many many years, does actually not exist, and Hattrick simply forgot to take it out of the rules again.
But if you are looking for evidence the kind of a 100% proof, then you need the calculations that are actually used, and we will never get those, so we won't get any further than the rules bring us. I am inclined to believe what is in there, because quite simply we have no better source giving us info. This is nothing that could be tested to make sure how it works...
They are not your friends; they dispise you. I am the only one you can count on. Trust me.