Topsy turvy

Rule of thumb, or follow the
Vernacular guidelines, in the
Patois of compliance, do as
You are told. That's a rule of
Thumb. Obey, execute, do as
You are told. Comply with, be
Observant and fulfill orders.
Adhere to whatever, although
It's not scientific or evident or
Based on evidence. It's a rule 
Of thumb, it approximates the
Rules that ought to guide us,
But is not so precise as to be
Demanding or insistent. It's a 
Rule meant to be followed on
The bias, zigzag, not a straight
Line. It's a rule of thumb which
Is not so much a rule, as a bit
Of a guideline, a suggestion to
Think on. Rule of thumb is no
Rule at all, with the thumb on
The scales, justice is turned to
Injustice, the scale unbalanced
Unhinged, the rule o'erweighed 
By the print of the thumb, rules
Crushed. The scales overturned
The rule of thumb gone astray