My toilet became plugged & needed a plumber to fix it. Is this wear & tear, or is my landlord responsible?

You sound like you are under the impression that dirt is part of "normal", it isn't, you are incorrect. If the tenant agreed to carpet cleaning and signed a contract to that effect it is enforceable even with the absence of dirt. The two issues, a contract to clean the carpet, and normal wear and tear are not associated with each other.

NOPE - Dirt is never wear & tear. It is not only legal but quite standard to require a professional carpet cleaning. It does not matter if there are no visible stains.

It is not unheard of for a carpet to be visibly clean but have the water come out black when professionally cleaned. There is always deep down dirt that you cannot see with the naked eye. You obviously knew about this rule.

The time to dispute this was when you signed the lease. Once you signed it you agreed to it. "Meaning if at my lease end, I leave my carpets clean and vacuumed, no stains just normal wear and tear.

I can legally disregard my lease provision that mandates professional carpet cleaning?" NO! You can never disregard ANY provision in your lease weather you agree with it or not.

You are not getting out of paying for it so you may as well just deal with it. EDIT: If the lease specificaly states a professional clean then renting a cleaner will not be accepted Even if you do that they can still charge you for the professional clean as required.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.