I had some more time to experment with the embedded stuff. It seems to run fine under Sure Fire, but:
When I run the unit tests in my IDE (IntelliJ IDEA) on Windows, the test JVM doesn't even start because the classpath from jboss-as-depchain's transitive dependencies is too long for the command line.
When I run the tests in the IDE on Linux, the embedded AS starts to boot, but fails... presumably because I don't have the 'extra classpath' stuff in there.
Maybe it would be better if I used the 'launcher jar' from the minimal cp example? That might reduce the number of dependencies if it's a jar-with-depencencies, as it seems to be. Also, is there any nice way I can stick the 'extra classpath' stuff in my IDE?