I wholeheartedly agress that the founders did not like the ides of secession.
I will also agree to your paraphrase of Jefferson, although IMHO there is no NEED to determine intent as the document is clear and concise in its meaning. We to often rely on the writings of the founders to squeeze out meaning!
Also, IMHO, the people granted certain limited powers to the national government as it was better suited to performing several functions (defense, etc ...) then an uncoordinated band of individuals (states included ...). If the people did not expressly grant a power, it was not granted!
I also believe the term Constitutional Rights is a fallicy - the consitutuion grants NONE at all! The people reserved the power to determine thier rights to themselves. I share Hamilitons opinion on the BoR’s for exactly the same reasons he used.
So, based on that premise - I reserved the right to determine whether I desired to be governed by the national government. As I am an individual, my only option is to leave the Union - with my movable property! - and the Government can not prevent me from doing so (I can not remove immoble property from the state without declaring myself a state). If the citizens of my state all agreed with me, we could, collectively as a State., remove ourselves - and our property (the State) - from the Union.
I admit - the argument is carried to the extreme and as an individual, I would at some point HAVE to submit to some government as the idea of individual sovereigns can only exist under a government as originally conceived in the US!
This is also not a recipe for longterm survival of the individual, nor a state - but just because it is a bad idea, does not make it illegal under the constitution (unless Kagan is ruling .... :D )