A Trinitarian would consider anyone who suggests "The Father is the Son" to be harboring heretical doctrine.
The truth is, though, that you are supporting your friend and not what he, for the sake of debate, tiptoed around.
"A Trinitarian would consider anyone who suggests "The Father is the Son" to be harboring heretical doctrine."
Only a Trinitarian who didn't understand the Trinity would hold that opinion. God is One, is He not?