There are a lot of specific rules and wordings in DnD. Even in 5e where it is streamlined compared to earlier editions, there is a lot to remember. The cast DOES help one another out sometimes. However, for every person to be focused on remembering the rules for everyone else would distract from their ability to just play the game. Rules get forgotten both ways, and it evens out.
Additionally, if Adam makes a challenge and knows they have the means to solve it (be it combat or puzzle or whatever) it should not be his job at all to tell the characters what they have to solve the problem rules or otherwise. If he did that, he's basically playing 75% of the game himself.
Finally, just so you don't intentionally twist what I just said there, that does not mean if the player sees they have X ability and are unsure if it applies, that Adam should not provide clarity or that the cast can't work together when there is a rules question.