Also very telling is the word "Guidance" which implies it is not a "Law" it is merely a recommendation, and if you choose to pay tax that is up to you.
Ultimately it is "Not a Law" until the courts rule that it is. This is the "only place" laws are made. Keep that in mind

Then you'd better pay the tax as a 'currency' if you're thinking that bitcoins are a currency. ('Currency' doesn't care about gains/losses like assets do, but GETTING the currency is taxable)
ANY income you derive be it from US currency, bitcoins or bananas, you need to report and pay taxes on.
Mining $100,000 in bitcoins is technically the same to the IRS as a bank truck crashing into your house in the middle of the night and 'depositing' $100,000 into your living room. You need to pay taxes on the $100,000 in either case.
Laws are NOT made by the courts. Laws are made by the Legislature (and other government agencies like towns, cities and states and even homeowners associations). It's the courts that decide whether a law is VALID and ENFORCEABLE or not.
Once a law is on the books, however it gets there, you must follow it, or you can be prosecuted for that law. If you choose to fight the law in court, you may do so, but you're guilty of breaking that law until the courts prove that the law is not valid.