Which is exactly what DiogenesLamp argues for -- a change in Founders' Original Intent based on Roger Taney's 70-year later reinterpretation.
Before Dred Scot no slave-holder and no slave-state considered it a "right" to take slaves into free-states permanently without freeing them.
So DiogenesLamp's arguments otherwise are pure sophistry.
Well, see there, now you've provoked a debate as to what constitutes "permanently." Obviously "six months" is not permanently, as Washington so shrewdly exploited.
But where in article IV do you see a time limit? I don't see a time limit in there. It seems to me like you are doing the "living constitution" thing where it means whatever you want it to mean instead of what the plain text says.