This piece of work sucks. I couldn't see anything at all. This is worse than that 'world's smallest pixel painting' thingy someone pulled off a while back that was simply a lone black pixel...
Seriously though, while I don't comment much myself, I always read the author's comments, and quite often - although not always, depending on length and average quality - also the comments of other viewers anyway, whether I intend to comment or not.
Mostly when I notice the description is full of typos and other horrid errors, as well as all capitalization, web-speak, or capitalization of every other letter, or perhaps as soon as I open the piece and see that it is basically a poem and it isn't put under that category or if it is a ripped off song and, by quick perusal, don't see a disclaimer for said song anywhere. Mostly, I just a short, terse, but overall polite warning, more like a "hey, heads up - this isn't a chapter/this isn't your work/not everybody will be happy to see that this is a poem when you made it sound like a story."
Wait - hold up... I've never done it one DA - normally if I'm not interested enough to look at the picture I won't comment - I'll just hit the x button. However, if for some reason I can't even get a partial view of the piece, I'll let the person know.