Like this - do that, one issue with cross-service pilot swapping is the differing training standards in use.
If everyone did a common course, it'd be easy, but as you're probably aware, Army pilots have trained differently to RAAF and RAN for a long time.
Seeing as there's been a bit of acrimony displayed already on the thread, may I point out that I'm not suggesting this makes anyone personally better than anyone else!
However, I think experience has shown that training everyone up to a wings standard that includes fast-ish TOT high-low nav etc. makes it possible to maintain that kind of surge capability we've been talking about, which has been used to good effect both ways in RAAF history (ie jet people to helicopters and vice versa). Many Army-trained pilots no doubt could perform just as well as RAAF / RAN ones, but they haven't been through the same mill and that makes it tricky when you look at slotting people into different roles.
Incidentally, this is why I don't really like the ideas mooted now and then about pre-wings streaming in RAAF pilots courses - I reckon we are too small an outfit to not maintain the flexibility provided by the system as it stands.
Anyway, that's a bit off track - perhaps chippymick can chip in with some comments.