You're giving the student the opportunity to believe that the sun revolves around the earth simply because he wants it to be true.

That would be an example of the gradual truthyfication of education. Truthiness is when we call something "true," because we want it to be true, usually without examining or understanding the evidence. It feels like it should be true.

To swing back around to writing for a second. University students are subject to the whims of all their teachers. Most will not "mark" writing, looking instead for ideas. As you say above (far above), every journal has its own style guide. I'm not sure about the US although many people prefer the Chicago Manual of Style. In Canada, the government, major newspapers, and educational institution agree that the * Oxford Canadian Dictionary* and the Oxford Canadian Manual of Style will be the current authorities.

Here's a line from the NASA History Writing Style Guide that says why consistency in style is a good ideal:

The purpose of style guidelines is to achieve consistency in prose style and usage so that readers can become absorbed in the content rather than be distracted by curiosities in form. Authors and editors likewise will have an easier task, composing and revising by the same set of rules. Guidelines are guidelines, however, and not laws etched in stone. Rules of usage, to serve their purpose, must of necessity strike a balance between custom, clarity, and principle.