Major Description
In DWPT we iterator over a document block and roll back documents if one of the docs fails with a non-aborting exception. Yet, we miss to delete those document if the iterator itself throws an exception. Given the fact that we allow an Iterable on IW we should be prepared for RT exceptions since these documents might be created in a stream fashing rather than already build up. IMO its a valid usecase if you have large documents to not materialize them in memory before indexing or at least we don't require this.