Yes it is perfectly ethical--but creates responsibility
The original question was, is it ETHICAL to buy a copy of the Running Light and memorize it beforehand?
I say, yes it is perfectly ethical to buy or borrow a copy. No ethical issue is raised. The book is publicly available. Some public libraries have a copy--might be a few years old but much of it is ageless.
Memorization in advance? Sure, why not, if time permits and motivation is in that direction. The advice to relax today and postpone the pleasure of the Running Light is advice in the opposite direction--and equally good advice. So you get to choose from opposite advice. Neither is wrong. Welcome to the adult world.
If you choose to dig into the Running Light in advance then understand, you are not a "fly way under the radar" type of person. If you are in front of your classmates on this, it's not so you can stand out and get brownie points. If you are in front, you have a responsibility to cooperatively raise your shipmates--classmates--to your level. You will get to help them learn faster, more accurately, etc. If you are in front, you are a leader. Way kewl. That's cadet heaven. But it's never an ego thing. You'll need help from someone on calculus, or knots, or something. You always need help.
Stress? Well, Swab Summer is all about stress, becoming different, morphing into something new. Growth. Stress. Gotta love it. Well, maybe not love it. Let's say, embrace it with a good attitude.
Good luck.
TWW '79