Of course, effectiveness is what 80/20 is all about!

But note that it is not necessarily about efficiency, though 80/20 does produce results with less effort.

It is primarily about effectiveness - producing the effects (aka results) you want in life!   

It is about, in a 20% mode, deciding what effects (results) are the vital, best happiness/satisfaction/fulfillment causers. 

It is not about making more money or being more powerful. 

Being able to produce more money per amount of time is only a vehicle to get where one wants to go, as is being more powerful.   But we want neither to go "too far", so far that they interfere with what we actually want that is more valuable.  

In 80/20, we stop when we accomplish the vital 20% and then look for the next thing that can be done to add a vital 20% to our desired results.  We make as much money as we need, in the least time possible, but we don't do it at the expense of stress or of losing happiness or health.  80/20 is always about balance, not dumb balance but smart balance - where we balance off our efforts based on investing them in the vital 20% and not going out of balance wandering into the low payoff 80%. 

To accomplish such effectiveness, you must learn 80/20 Time Management, including 80/20 Leveraging of your time and self. 

And, of course, you can't be effective unless you practice 80/20 Planning, so you know what is of value and how to get there.

For more detail and implementation, go to The Life Management Alliance site and enter these into the search engine or use the contents/links maps.