Asynchronous Content Aggregation

[Heinrich_Klobuczek/FIRNY/NorthAmerica/MCKINSEY-EXTERNAL%MCKINSEY-EXTERNAL%MCKINSEY]

I haven't found anything in Cocoon that would allow asynchronous content aggregation.
If a document is composed from several pieces whose generation and processing is time consuming, it would be desirable to create these contents in parallel before assembling.
Is there a way to do this or is this something still to be implemented?
Thank you
Heinrich