Matthew’s Use of Mark: Did Matthew Intend to Supplement or to Replace His Primary Source?
It's been awhile but I finally got to reading Sim's article. And according to Sim the answer is 'no' to supplement and 'yes' to replace. Here is Sim's view on this point:
Whatever value Matthew placed on Mark, he still viewed it as an inadequate presentation of Jesus’ story that required correction, improvement and expansion, and which needed to be updated to meet the needs of his intended readership. Once we acknowledge and understand the extent of Matthew’s dissatisfaction with Mark on a wide variety of issues, the common view that the former largely embraced and affirmed the outlook of the latter looks decidedly shaky.Sim claims that Bauckham's view also sees Matthew intended to replace Mark. He points out that the Gospel of Mark did almost vanish in the second century. Thus:
...That Mark sits within the New Testament amidst the other Gospels and right next to the Gospel of Matthew is, in view of the argument presented in this study, more than a touch ironic.
Anyway I have to get back to other matters today, namely thesis writing.