I had a good teacher....This was a lesson I learned some time ago when I was working with extreme macro. I had a shot where I wanted to create a guess macro photo. Them in and of them selves require some element of abstract however there is a point where the photo can go beyond a guessing game and into the relm of true abstract.
This image did just that, Overshot macro guessing game material and straight into abstract. When I asked about why it failed, what he told me was what abstract was. I just thought I would pass along the knowledge.
The personal opinion that my experience has lead me to is that abstract lines are easiest to find with good macro equipment and deep DOF's. Though not necessary, it is much easier.
I guess I am a bad teacher.

But at the same time, not one person has asked me to define what is and isn't abstract. This project was to teach you to look at the world around you in a different way. In this case to look for compositions made up of line(s). I disagree with it being "easiest" with a macro lens. I know it's your opinion, and I don't mean to be "combative", but interesting abstract compositions are all around you. You need to look at the world differently, though. None of the following examples were taken with a macro lens, at close focal distance.
[IMG - pulled for space]
The purpose of this project was to think purely about composition. It isn't to teach one to become an abstract photographer, but the value of this exercise lends itself to many other styles of photography.
Wile it is true that a good teacher will know exactly what they are asking their students to accomplish, it is human to misscommunicate. When I orginally replied to this thread I had absolutely no clue what the "Bitter's Evil School of Photography" was about....infact it was whay I looked at this thread, I was curious as to why I had been seeing (BESP) so much lately. Afther reading the OP's statements I opperated on that assumption that this was about true abstract works. It was not untill after I had made my second post that I actually went and looked into the assignment. Out here in open forum my statements still hold any merrit they held when I posted them as the OP was looking to get abstract.
Once I had read the assignment, I understand how we have come to this conversation. I did also notice you had a disclamer in the group discription that covers you in just this sort of instance. So I'm not going to say you are a bad teacher, we've just encountered one of those moments you've been looking for your self when you said something about learning about the things you don't know by teaching the things you do. Internally with the group this likely would not have occured because as you said no one asked.
But since it has come up, The statement pertaining to abstract was.....poorly placed for lack of a better phrase. One does not need to create abstract art to use lines nor does the image need to be representational. You are right, lines are everywhere and can be used in a couple different ways artistically. Artistic does not necessarily make or require the image to be abstract.
A few of my artistic uses of lines that I would not consider abstract:
eg.#1 O'Da...I Mean - Focal length: 50mm
eg.#2 Please Share - Focal length: 400mm
eg.#3 A Life on the Line - Focal length: 400mm
But here is the real contradiction to the abstract statement. One often finds that artistic thought and vision are needed to provide artistic use of lines in non artistic representational works.
eg.#4 Black Capped Chickadee - Focal length: 400mm
This shot was composed before the bird even landed, The bars from the feeder maticulously placed at both lower corners specifically to draw the viewer to the bird...Thus is why the bird is out of focus :neutral:
Some times you need to think artistically during composition to see the one line that will bring them all together.
eg.#5 Proximity - Focal length: 35mm
Without that pole the powerlines would have been scattered and intruding, incorperating that one pole provided all of those lines a home and gave them some leading qualities to account for the additional space needed to incorperate the pole and still help the viewer find both of the subjects in the one photo.
But anywho....it's after two thirty in the morning and I need to start shoring up for the night because I have to be up by eight in the morning....