Just curious, what part of the Constitution says that the Constitution can "imply" delegated powers to the federal government? Secession is not mentioned in the document, correct?
Therefore, secession is neither delegated (dictionary.com defines this as "committed") to the federal government, nor is it prohibited to the states. How does congressional approval fit into this, then? The congress, constitutionally, cannot self-delegate powers that are not already given them because such powers "are reserved to the States respectively, or to the people".
I'm afraid I fail to follow your leap of logic, FRiend.
Check the quote in my message 28 and tell me where Chief Justice Marshall is wrong.