Current ROI and evaluation work may be a bit premature because many learning professionals continue to disagree on how workplace learning actually occurs. At one end of the spectrum are instructional designers who insist that only formal learning methods are valid. At the other end are workflow learning advocates who maintain that trying to design courseware to effectively deal with accelerating information overload is a fool's errand. Because this group claims that approximately 80 percent to 90 percent of workplace learning occurs informally, without a performance test or a learning management system in sight, they insist that practitioners should focus their limited resources on facilitating informal learning.