Since the early 1990s, a variety of studies has shown that network traffic, both for local- and wide-area networks, has self-similarity properties. This has led to new approaches in network traffic modelling. Instead of developing completely new traffic models, a number of researchers have proposed to adapt traditional traffic modelling approaches to incorporate aspects of self-similarity. The motivation for doing so is the hope to be able to reuse techniques and tools that have been developed in the past and with which experience has been gained. One such an approach for a traffic model that incorporates aspects of self-similarity is the so-called pseudo self-similar traffic model. This model is appealing, as it is easy, to understand and easily embedded in Markovian performance evaluation studies. In applying this model in a number of cases, we have perceived various problems which we initially, thought were particular to these specific cases. We briefly review the pseudo self-similar traffic model and discuss its fundamental shortcomings.