I find most of these 8 rules of X too vague to be useful. What would be useful is to have an example on how to get it right and how to get it wrong for each one.
I swear someone posted about a new site which basically has a list of good ideas for blog topics. What you just suggested would be good on there.. anyone remember what it was?
"Permit easy reversal of actions" is kind of a toughy and rare among web apps. Also not quite an interface item as it takes some substantial functionality in the code to accomplish.
B-
Users don't care about it being "tough" or "rare", they just want it to work.
And decoupling interface thinking from code is a mistake.
Schneiderman talks about this in some of his papers: design the interface, then write code.
So it's hard to write programs that aren't steaming piles of crap. Your point?