I like most of these except the one about not using !important.
I use .flat { margin-bottom: 0 !important } to remove the default bottom margin from certain typographical elements (ie. h1,p,ul). In this case where I absolutely know that I mean what I say when I apply that class, it works great.
For me shame.css doesn't necessarily contain hacks. In mine you will find less thought out selectors that are added in haste and anything else that doesn't conform to the high standard I set myself.
I use .flat { margin-bottom: 0 !important } to remove the default bottom margin from certain typographical elements (ie. h1,p,ul). In this case where I absolutely know that I mean what I say when I apply that class, it works great.