That statement is very true and I feel that it is the mark of just about all great writing. I myself have written many poems over the years – even though I have not put pen to paper recently due to a lack of real inspiration. The thing I liked to do most and the thing that I liked to read most where those vague lines that always seemed to open up a world of possibility other than give a direction to the reader to follow. When enjoying reading, especially in the case of poetry, I think that most often the reader should be allowed to form their own ideas and images from the words they read, even when it is prepared by another hand.