handwaver

Someone who engages in handwaving.

Take his predictions about our technological and business-development timelines with a grain of salt, because he's an inveterate handwaver.

It is easy to lose sight of the fact that the oversimplified model that is eddy diffusion must be used with care and with a great deal of auxiliary physical insight. Well-educated handwavers often produce more useful results than the people who concentrate on the mathematical and computational aspects of the problem. The ideal is a suitable combination of the two. One way to become well-educated is to study various limiting cases that can be solved analytically. Indeed, these solutions can take us surprisingly far into many problems, sometimes rivalling what can be done with a computer. The substance of this article is a summary of the available solutions, and a critical compilation of eddy coefficients for the atmospheres of the Earth and a few other objects.

Someone who engages in handwaving.

A gifted pupil might sometimes need to be coached privately about avoiding presenting themself as a handwaver.

The very intelligent pupil soon becomes bored by the repetition and sits aloof and inattentive, or he becomes a "handwaver" and thus draws upon himself unwarranted and sometimes open rebuke by his classmates.