If one has details that the other lacks (and vice versa) the accounts are likely independent. If the accounts help / complement each other the likelihood increases.
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No one doubts the Markan priority. Matthew used Mark and tried writing a better version. Matthew added details. But they were made up?
Going further Luke added details and John added all kinds of supernatural wu.
You are talking about historical events where things actually happened. This is not that. It isn't that style. Matthew added zombies roaming the streets and an earthquake. This does not increase the likelyhood they are independent? These stories add details and SUBTRACT just as much.
A lightning Angel of the LORD? Was MISSED in other versions? Nothing here is likely independent even without all the other evidence?
Mark has no guard. 3 women. Mary, Mary M. Salome. The stone rolled by itself.
Matthew added a guard because people were saying the body was just stolen. Now just 2 Marys show up. Earthquake, Angel of God shows up, he's like lightning and the guard is scared. The angel showed them where Jesus was. The angel also rolled the rock back to open the tomb.
In Luke it's 2 Marys, Joanna at the tomb. The rock is already rolled, 2 men in shiny clothes are in there?
John has just Mary M see the stone already moved. She got Simon Peter, they saw 2 angels sitting in the tomb.
In all cases when they see Jesus is different.Gospel
Any rational person can see this is a made up story. Each Gospel was meant to be THE Gospel of Jesus. They were not writing a series. IF they were they would have taken care to get the story correct. The historical consensus is that in 367 they chose the 4 churches that were in Rome and doing the best with membership and finance and were most favored by Constantine.
This caused the need to attempt to harmonize the Gospels the best they could.
Nothing about these versions "enhance" each other. The authors were clearly making it up based on a basic outline.