A two-part study manipulated structure demands (sequencing ideas, forming sentences, and complying with punctuation/spelling mechanics) in a persuasive writing task to measure the resulting effects on content operations (generating arguments/propositions). In part one of the study, 40 graduate students wrote preliminary and final drafts in one of four conditions that varied according to the amount of structure demands. It was found that the elimination of each structure operation increased the production of persuasive arguments. In the second part of the study, 60 undergraduates wrote their preliminary drafts in their "typical" writing strategy (control group), in an unordered-proposition format (no structure constraints), or in a polished-sentence format (structure constraints). The writers with average verbal ability benefited more from the elimination of structure operations than did writers of low verbal ability. In the control group, writers with average verbal ability usually selected proposition-based formats (outlines and diagrams) that dispensed with the need for structure operations. Writers with average verbal ability also produced more sentences, more arguments per sentence, and fewer errors in mechanics than did writers with low verbal ability. Overall, the results were considered empirical justification for the use of freewriting techniques, which eliminate premature editing that can block the production of ideas. (RL)