Halliburton did it?

Botched the cement job on BP's blowout well in the Gulf. Long article in the Wall St Journal. But some things are unclear. The Journal speaks of Halliburton whipping up a new cement recipe for the BP well.
That's a little weird. We have had decent cement since Julius Caesar's time. The Pantheon in Rome with an enormous concrete dome, was built by an army buddy of Julius Caesar and is still in service today. The Romans built the harbor at Ostia with hydraulic cement that could harden underwater. You would think that a good cement recipe for oil well work had been developed years ago. Had I been the BP manager on that rig, I would have demanded that Halliburton use a well tested standard cement mix and not fiddle around with custom stuff.
The Journal also mentions that cementing oil wells is a tricky business with a high failure rate. Something like a quarter of cement jobs leak. This means that proper engineering practice is to test each and every cement job. This testing was omitted on orders from the BP manager on the site. So, that makes it BP's fault in my book.