9) *** Section 4.1.3. *** 
I think it would helpful advice to users (and implementors) to
make a comment on what users can assume (or not) about the semantics
of "Executable" and "WorkingDirectory". They might be fairly well defined
for a (non-parallel) POSIXApplication, but they are potentially ambiguous
when re-used in the context of SPMD (parallel) applications.
Thus on a cluster environment, can it be assumed that the pathname of the
executable is necessarily the same on every worker node?
More importantly, can it be assumed that every process of the parallel
application will have WorkingDirectory as its working directory when
it starts? In general, I think the answer is no.