Oracle BPM Suite vs. BPA Suite

Yesterday I still had some questions in my article about the Oracle BEA acquisition. One of them being the mist I had between Oracle's BPA Suite and the BPM suite. There is however a pdf of the presentation that belongs to the webcast of Thomas Kurian. It can be found at: http://www.oracle.com/products/middleware/docs/oracle-middleware-strategy-briefing-072008.pdf. In the pdf is stated that:

• BPA suite is meant for rigorous process modelling
• BPM suite is meant for agile process modelling

So that clears things up, right?
If it does for you, you may explain to me what Oracle means by "rigorous" and "agile", why should I put (more) energy in learning BPA Suite, and why is Oracle spending money in closing the life-cycle-wheel in the BPA Suite-BPEL-BAM round trip? It's kind of contraditory I think: BPA Suite for rigorous process-models generating BPEL bleu-prints that is clearly meant for a SOA and one of the main drivers for SOA is having agile enterprice business processes.

I think I have a feeling about BPA suite and the use of it in larger enterprises and having business process modelled that are not that agile. That turn out to be more rigid.
But is there an enterprise that is going to use both suites? Doing their "rigid" business processes in BPA en the agile in BPM both generating BPEL for the "Converged" process engine? I would not think so, but I'm probably not so visionary as the Oracle VP's are. Probably you would use one of the two suites and if you choose for BPA suite, the more agile processes that you don't design with BPA, you probably design and build directly in BPEL Designer in combination with good old MS Word/OpenOffice Writer.