No one ever said it was the same! The moral theology of the Church does not say it is the same!

There is a certain amount of maturity expected of an adult woman. But liberals here on this forum think that woman are perfectly mature and almost never need correction.

As BW says we just need to be "NWICE..."

I think that in our culture that this would not be practical.  It would be illegal and considered grounds for divorce.  
However, understanding that it is theoretically something permitted by Church teaching might help us have a greater appreciation of the husband's authority.

As I understand it, original sin makes the experience of being subject to one's husband often difficult and unpleasant. But I do not think that subjection is intrinsically a bad thing.  Relationships are often, by nature, hierarchical.  To be under authority and to obey another is clearly a good thing in some cases.

I cannot actually think of any cases.  I only said "some cases" to allow for overlooking something.

No, subjection is the direct result of Original Sin.  Original Sin didn't simply make it "often difficult and unpleasant".  Before that there was a naturally harmonious complementarity with an active role (man) and a more passive role (woman).  Subjection is a violent way to restore the natural harmony that was severed by Original Sin.  This has to be forced now whereas it was just naturally there before Original Sin.

Like the punishment of the state, there is liberty given to the discretion of the husband. What it does say is that it is for serious matters.

  And what of true tolerance, specifically of error?

   There is a distinction to be made regarding what may be permissible in principle, and what is or should be avoided as imprudence, i.e on another principle, such as is the case with tolerating a evil to avoid or mitigate a greater evil.

   I think that this is part of what you are attempting to express, but please clarify either way.