Cannot test at this time, but I have an a priori comment. Having multiple agenda buffers around increases the probability that you will change the outline buffers before you perform an operation in the agenda. You might do this either by performing agenda commands in an agenda buffer or by directly editing the outline buffer.
As the agenda uses markers to get to the outline buffer, this increases the probability that you will perform an operation that will corrupt the outline buffer. I have not thought about this deeply, but perhaps every agenda command should perform a rudimentary check, if possible, to make sure the marker still points to where it did when the agenda in which it was called was created. This might entail storing header strings, or the like. It might not be ideal. However, I have noticed buffer corruption in the past and I think it would be good to keep this risk in mind in case we can come up with ways of making agenda commands safer. I avoid using the agenda because I don't always know if the marker still points where it should. Hope this helps. Samuel -- The Kafka Pandemic: http://thekafkapandemic.blogspot.com
