Well, the usual layout is that if you follow a certain skill tree, then you will get some sort of bonus. Almost every game has that, nowadays, even King's Bounty.
The underlying philosophy is that people should get rewarded if they manage to specialize. And stick to their once chosen path, no matter what. Flexibility, however, is not rewarded. The common view on that is that "anyone can do that" - and thus "Jack-of-all-trades" are always regarded inferior to specialists. Just look at (A)D&D games. I currently perceive it with DDO. Build Masters frown upon Multiclassing, "except when you really know what you do". Plus, Multiclassing in DDO doesn't get a a certain feat called in community a "capstone". Even worse, the game apparingly seems to be built so that non-specialists have a very, very, if not impossible time in what they call "end game", at least everyone there says so.
Is this a mirror of real life ? especially of the "nerd" cliché ? That specialists (and sometimes even *extreme* specialists ! are rewarded, and flexible ones not ? Who needs a flexible person in Nerd Life anyway ? You don't need to learn cooking, for example. There are Pizza delivery services.
Argh. But I disgress - in the end it's the Larian team's decision anyway.
