> Makes me wonder ... should it be API? > Dirk, was your intent to add API?
As far as I can see, PerspectiveDescriptor is part of the compat layer. Therefore, no it was not my intention to add public API, as the whole class should be internal.
Regarding the exported packages, I also heard that it was due to laziness. But the only tooling I know that would make it easy is BND tools. And since all Eclipse projects are created using PDE, this would be a really huge task to switch. At some points not even possible because bnd doesn't know about features and products, and therefore a simple switch is not even possible for Eclipse projects.
I was thinking about a possible integration of bnd and pde in some way, but currently there are only solutions using Ant in the middle somehow, and that doesn't feel like a clean solution. For example, bnd generates the MANIFEST files with the correct semantic versioning for you. But as it is generated, it doesn't exist in the project. Therefore you can not use the PDE tooling for creating a feature, because at development time there are no bundles PDE can find. Quite complicated topic and gets even more complicated when thinking about automated builds.