I would question who that “gifted expert” might be? Perhaps a Martial Arts Individual?
As for one being rational or not...by what/whose measure is this defined?
Anyone can create a sliding rule of rationality based on the very beliefs they may have, in whatever area of study they are in or practice. It’s done all the time.
The question will always remain...at what point does the break from reality occur...there is always a root where their involvement in something begins....from there it increases but there is always a start.
As far as defining rationality goes, there is an odd exercise that seems particularly effective in fine tuning and centering the rational mind. It’s called mathematics. Seriously, it is used for just that purpose.
The basic principles of shifting awareness are simple and straightforward, have background explanations, and strip the mysticism out of it.
To start with, at some point in the distant past, the human species reached an agreement on a standard point of awareness, a common reality. This shared “frequency” as it were, was optimal for survival in a dangerous world. Though there is considerable variation in it, a person right smack dab in the middle is unusually rational. Not many people are naturally at that point, most are off to some degree.
But there was the additional problem that people’s minds tended to wander, to either a state of more intense focused concentration, or a less focused, more inspirational state of mind.
So people, again in the distant past, invented a technique universally taught to children even today, of an internal dialogue—talking to ourselves. It keeps our minds from straying too far in either a focused on unfocused direction. Instead we vacillate around the standard mind set. A much better place to be if you are being pursued by a hungry tiger.
But today, hungry tigers being in shortage, lots of people try to turn off that internal dialogue, so that their minds *can* shift out of neutral into a more focused or more unfocused state. This is why being internally quiet is important to prayer, meditation, artistic inspiration and a slew of other things.
Those who practice exercises to get more control over their internal dialogue generally enjoy doing so, because having a better ability to concentrate, on written tests for example, improves test scores solely because you aren’t distracted—and likewise, if you are trying to be creative, you can get a better handle on inspirational ideas, without some voice chirping in and disrupting it.
How far a particular person can go with this, once they have some control over talking to themselves, is based on how much internal energy and chutzpah they have, and how well and long they can hold on their new state of mind.
Not surprisingly, even religious people who overcome theoretical objections to the idea usually find that their prayers are deeper, more substantive, and more emotionally rewarding if they are not as distracted when they are praying.