This is one of the rare times i want to complain to opensource devs, but i can't help it. While you have are gratitude for your work, there are some things that shouldn't be happening.
Why HD2000-4000 are second rate citizens? First AMD drops support in Catalyst for them. And while it would make sense to have a focused opensource driver for these generations to provide legacy support, it seems that the opensource driver makes a priority Evergreen and above generations too... A while ago it was the news that Evergreen would have official OpenGl 3.0 support on by default, earlier than the older generations(?), and now from what agd5f says:
a) Either evergreen will have support for hiz first
b) Or hiz support for hd2000-4000 was fine but there were issues on Evergreen so they decided to hold it back...
Either way, it is a bad attitude towards older generation users. Why Evergreen and newer are a priority, when they can use the Catalyst and are much newer chips? Seriously, i own a 3870 and it is about 2 year older than the Evergreen family. When i see that Evergreen matures to OpenGL 3.0 first or gets Hyper-Z(a really important feature) first (not to mention other performance improvements etc) i feel cheated. It is like AMD showing us older generation users to buy newer cards. Well, if that is what they want, it would be better to just ask for it, not this way... And why upgrade? My 3870 does its job perfectly...
I think you are forgetting how the developers work and assuming conspiracy where none exists. In general they will work on a new feature for all generations (in this case 2xxx through NI) but things will start working on one generation before others as a consequence of generation-to-generation quirks. The developers don't choose this, it just works out that way.
If you are saying "developers should be forbidden from working on newer generations until everything is finished on older generations" then the overall rate of progress would drop dramatically, since it's generally a lot faster to write code for a new feature designed to work across all the generations supported by the driver than to only look at older parts. In this case hyper-z and the backend work are pretty interdependent IIRC and both were happening at the same time, so it seems to make sense that Jerome would have had an Evergreen card in his system when it all came together.
Anyways, key point here is that most of these features are implemented for multiple generations at the same time, and it's luck of the draw which generation starts working first. If you assume conspiracy or lack of care for older hardware each time that happens you're going to be whipsawing between happiness and misery for no good reason. You probably owe the developers a bit of an apology.