How does a Parliament legislate for a State ? For J&K, IOA enumerated the three matters. But, for the rest such as tax et al, State had to be consulted.

First a constitutional entry has to be made applicable to the State and then the Parliament can legislate the law. Art. 370 found a different way which left it to the State Govt.

If 370 goes, then Art. 1 also goes, along with other Articles. There was a deliberate intention of retaining the Article. Doing away with it would entail that you are snapping ties with the State : Shah