When Do Instructional Features Become a Distraction?

Would adding instructional elements to minimalist-based instruction increase the rate and retention of learning? Logically, it might be expected that providing learners with additional instructional aids would result in increased learning. Conversely, I found that the additional instructional features actually distracted the learner from the critical instruction, but not significantly. Furthermore, learners tended to skip over anything they perceived as extraneous.