You are right, Dragosh, thank you for your ideas. But it's considered from your individual point of view. What we need is to think about SP system as the complex. The age of SP managers definitely isn't the main and/or only variable causing that somebody is trickeable and the other isn't. Maybe one is not really interested in the game, another one has influenceable personality, etc., that're the possible causes, right. But definitely there is a part of younger players who are not so smart, just the same way as there is big part of older managers who are not interested in game enought to resist all the tricks.So,even if I am 16 years old, I don't play any other online games, I don't have any knowledge about marketing or economy I still couldn't be "tricked". So if a manager can be tricked, he can be tricked no matter the age, because he is not really interested in the game or his personality is influenceable, things that you can't change.
But what is bad for SP as a system is the fact that there is some group of managers who are actively trying to make profit from such a trickering. It's very similar to zandyy's original problem with "negotiating cheaters".
And this problem has two possible solutions: a) let it be as it is, or b) try to improve SP system somehow to make it impossible. Zandyy started this topic with intention to try the b) variant. Although I rejected such a try to change the system at first, I changed my mind then. I'm open to ideas about "fixing" SP system some way to reduce cheaters/trickers possibilities now.