For those that are interested, Bp published their report on the findings of the internal investigation of the Macondo Blowout.
It's fairly complex (Tasche, you will probably be the only other NS who understands this fully) but there is a lot of detail in here about what happened.
http://www.bp.com/liveassets/bp_internet/globalbp/globalbp_uk_english/incident_response/STAGING/local_assets/downloads_pdfs/Deepwater_Horizon_Accident_Investigation_Report.pdf