Don't get "hung up" on the names. They are generally rather meaningless when it comes to mileage earning, as you say.

You can always check which fare code each of your flights will book into prior to actually purchasing them. When you've made your selections, click on the Fare Rules link. This brings up a pop-up and you can see the fare basis code - the first letter will be the fare code for all flights on the illustrated sector. Be warned, though, that for return or multi-stop tickets, each direction is presented on a separate tab, so be sure to click on each tab in turn to check the fare code for each flight - your DUB-AUH-MEL (for example) might be in one fare code, but the return MEL-AUH-DUB may be in a different fare class with different earning rates.

Of course, if you book using a travel agent, you can always ask them (and even request that they book into certain specific fare classes, which you generally cannot do on the website). Also, many online travel agents also allow you to discover the actual fare class of each flight prior to purchasing - and you will notice that no-one outside of Etihad themselves bothers referring to fares using these generic, catch-all, and unspecific terms.

In short - you are looking for a nice, brief guide along the lines of "Economy Saver - Always earns 50%; Economy Discount - always earns 75%; Economy Full Flex - always earns 100%; Business Saver - always earns 125%..." etc etc. THE VALUES GIVEN ARE NOT REAL. I do not think that there is ALWAYS a fixed, deterministic correlation between the generic "name" and the earning potential. Always check the fare rules of the ticket you are interested in before buying - do not merely rely on the "names".

I have seen, in the past, some Economy Promo fares that are issued in non-earning fare codes. The thing that ultimately counts is the fare code of the flights you book. Not whatever name they have decided to group it into. Discount/Special/Promo names should raise alarm bells though - expect low, or non, earning fare codes. BUT YOU HAVE TO CHECK, the name is not enough to determine this.