Different physics problem types, i.e., the same physics scenario posed as a problem in different ways, can emphasize different learning goals for students and can be used in diverse situations to meet various instructional goals. We examined graduate teaching assistants' (TAs') views about broken-into-parts introductory physics problems within the context of a semester-long TA professional development course. The TAs were asked to list the broken-into-parts problem type pros and cons of, rate its instructional benefit and the level of challenge it might produce for their students, and describe when and how often they would use such problems if they had complete control of teaching a class. We find that TAs reported the broken-into-parts problem type to be the most instructionally beneficial of all the problem types and would use a broken-into-parts problem type often and in a variety of ways (e.g., homework assignments, exams, and quizzes). Written explanations and interviews suggest they preferred to use a broken-into-parts problem type more often because of the guidance such problems offer. While providing guidance to students is an appropriate instructional approach, our findings from interviews suggest many TAs may be motivated to assign broken-into-parts problems out of a desire to make the problem-solving process easy and/or less stressful for students, especially because they felt introductory students may not be capable of breaking a problem into sub-problems on their own. The instructional benefits of gradually removing the scaffolding support to help students develop self-reliance in solving problems appeared to be overlooked by most TAs. This lack of awareness or reflection on the important role that removing scaffolding support gradually and providing adequate challenge can play in helping introductory students develop self-reliance and become independent, expert-like problem-solvers has implications for the professional development of TAs.