Try not to smash clipboards on your knee (or the floor) while coaching.
It is dangerous: Clipboards can shatter and cut somebody. It would be unfortunate to cut a player (literally) with a jagged edge. If you slash bespoke slacks, you need to order a new suit, irrespective of the condition of the jacket.
It displays emotion: Firstly, treat the underlying emotion, then the technical problem. I have smashed a clipboard and it badly disturbed players. Rather than “firing the team up”, it increased their anxiety and decreased execution down the stretch. Players may be nervous about the outcome of the game – due to the pressure of the moment or the strength of the opponent – and the coaching staff should not add to this anxiety. The coaching staff should be a positive and nurturing presence.
Coaches should instil a sense of calm and ignite the killer instinct of the team. Raw anger can disrupt that focus and create uncontrolled fear or anger. Intensity must be channelled at the right targets, at the appropriate levels.
It makes outbursts of anger acceptable: Occasions when a coach should contest a call to the point of a “T” are rare and high school coaches should discourage players from arguing calls. Dissent has a time and a place and it should always be planned. Coaches should model the way.
It shows everyone up: I am doubtful that a professional team would appreciate the gesture because it implies that they are not working hard. I am confident that the officials would not care for the gesture because it implies that they kicked a call. As I mentioned, because of personal experience, I am positive that high school players would be terrified by the gesture.
It is difficult: You really have to put a great deal of force into the clipboard, especially the plastic ones.
Nevertheless, it proves that in order to coach, one must understand that all leaders (coaches, teachers, mentors) are humans and therefore flawed — even those at the elite level.