This is definitely a good idea. Knowing who this person is in your workplace will make life much easier. In some workplaces though is it a little more difficult to identify who that person is.

In a previous workplace, I was this person. But it was a workplace that was not based on book knowledge, it was based on knowledge of processes to achieve the end goal.

An unfortunate side effect of being this person at times is that you can end up burning out from all the demands from every direction.