A bit off topic bit this is the first I have heard about asdf-bundle and its coming inclusion in ASDF3.  Is it possible to get it to return a plain text source file instead of a fasl?  I have been working on something to do that (return a source file that when loaded is "equivalent" to an asdf:load-op, which hopefully across implementations) but I would much rather see if this is already a solved or easily solved problem via bundle.  Plus attempt is a hacky POS, but I bet that is more or less unavoidable (because of the desired cross imp requirement and the complicated nature of the Lisp reader).
Zach KS