Flerfspective is a term for the butchered mess that flerfs make out of linear perspective when using it to explain:

sunset
hull down ships
why we can't see China from directly over America
a variety of other phenomena

Vanishing Point Issue

A key misunderstanding is that flerfs think the vanishing point lies at a finite distance from the observer, when it's actually infinite.

The elevation angle of Rowbotham's sun would decrease as it moves away horizontally, but an elevation of 0° is the infinitesimal limit of this series.

In other words: the sun could recede horizontally forever, but could still never actually reach 0° elevation.

Rhetoric

Despite extravagant, ongoing efforts among globers to explain the above issue, to date apparently no flerf has ever comprehended it (except ex-flerfs).

When confronted on it, flerfs generally become chaos gremlins and rebut with statements like:

"The atmosphere magnifies things."
"Using an orthographic diagram to explain perspective is a category error."
"Math is a language, and can be used to lie just like any other language."
"We see in hyperbolic geometry, not Euclidean."
... and many similar piles of nonsense.

For this reason, the "flerfspective" concept is a rich source of word salad.