Aid Another

The rules for aid another seem pretty cut and dry:

A creature can affect a particular check only once using the aid another action. However, up to four creatures can use aid another to effect a single check, for a maximum bonus of +8 or a maximum penalty of -4. In certain circumstances, the DM might decide that only one, two, or three creatures can try to aid a check. For example, it is unlikely that four creatures can assist in picking a lock.

But what about knowledge skills? Don’t the knowledge skills represent a body of knowledge? You either know it or you don’t. Well, not necessarily. There have been many times where I’ve been discussing a topic with another individual, only for a small piece of information to be just outside of reach; on the tip of my tongue, so to speak. Then the other person says something that jogs my memory, and everything falls into place.

A clear case of aid another on knowledge check if I ever saw one. In the end, aid another can be used on any skill, as long as the players can roleplay their reasoning.

For more discussion on this topic, visit the thread I made on EN World.