|For starters it will confuse the switch as switches identify each pc by their MAC address, they store these address in a table in memory and hence is why each pc has to have a unique MAC address. |
I don't know exactly what will happen, maybe the data will be broadcast to every pc with the same address essentially turning the switch into a partial hub.
It is a totally unnecessary thing to do..
As for ip assingment by the DHCP server that shouldn't affect anything as the the DHCP client on the pc requests an ip from the DHCP server on the router, so it is MAC address independent as far as know...