Sirius Glass
Subscriber
Funny. There was a time when I took great pains to avoid splitting a photo into two equal halves with the horizon, a tree or anything else. I also jumped through hoops to avoid telephone poles, power lines, road signs, etc, in my photos. I was shooting slides, so no cropping.
A few years ago I enrolled in a medium format photography class at my local university. As part of that class, I was assigned the task of discussing the photography of Lee Friedlander -- perhaps because the instructor noticed I was interested in similar subject matter. At first, his telephone poles - sometimes right down the middle of the composition - made me crazy. I am pretty sure that's why he did it -- a middle finger for the rule makers. Now you will often see powerlines and telephone poles in my photos, too, though almost never on a midline.
As for the composition under discussion, I prefer @Rolleiflexible's version in post #43. In every version which includes the couple on the right (ground level) I am bothered by how close to the edge of the frame they are. Like, fingernails-on-chalkboard bothered. I am sure they are very nice people, but I am happy to be rid of them.
One or a few right down the middle compositions are fine, but many of them become static and boring. That is the reason for the guideline.