Oolite Bulletins

I somehow was under the impression that all NPCs of the original set used to have a unique role in their set, of the style "oolite-adder", "oolite-anaconda", and so on.

To my surprise, when I recently opened shipdata.plist, those unique roles weren't there, only the generic ones. I cross-checked with Oolite 1.65 immediately, and also there were no unique roles in the shipdata.

So I'm asking myself: have I hallucinated the presence of unique roles in the original set, or did this exist as a feature in some intermediate version(s)? (It is also possible that I have made this tweak myself, and it was overridden when I installed a new version.)

Also, if it did exist, why was it removed? Or, if it never existed, wouldn't it be a good idea to have something like that?

I also give you an example for how unique roles can be useful: recently we were debating flaws in the setup of the escorts of launching traders. In order to test this, you have to launch a trader with escorts. Currently you only can launch a hip with role "trader", which produces just any trader, and most of them don't come with escorts. So it would be handy to be able to launch specifically an Anaconda, which comes almost guaranteed with escorts.

That's strange.
As it happens I am (right now) cross referencing aspects of my Smivs'Shipset shipdata.plist with the current 'core' shipdats.plist. As you say the current one does not include these, but mine does! Mine is an edited copy and paste from a previous Oolite version, so they certainly were there. Oddly, I thought mine was based on the v1.65 shipdata.plist, but it might have been a previous one...I didn't keep a note of which one I used and should have done.
Still, I can confirm they were there, and they do still exist in my shipdata.plist.

IIRC those unique roles were present as recently as 1.73.x

The oolite-* roles were removed from the core shipdata.plist by Ahruman on September 7th last year, on r2423. The commit log reads:
Removed badly-thought-out supposedly-unique roles for built-in ships

There is no further information as to why the unique roles in the shape and form at the time prior to that commit were not good enough.

Probably Ahruman wasn't satisfied with "oolite-" as prefix, because a OXP ship designer could use that as well, thinking that their new ship is also for Oolite?