The Case Study of EVR by Eslinger and Damsio, can be used to oppose the WMM. Evr was a patient who had had his cerebral tumour removed.
When tested, EVR performed well on tests requiring reasoning,which suggested that his central reasoning was intact,however he had poor decision making skills, where he would spend hours trying to figure out what food to eat. This suggests that his central executive wasn't fully intact.
If EVR's Central Executive was not fully intact, but was partly working, this means that the Central Executive is much more complex than the Working Memory Model Suggests. The Central Executive must consist of several componets and must not be just a single component.