If you don't receive a neat solution to that, you could always just create a second attribute to temporarily store the incremented value, and then copy that value back into the original attribute, by either a copy rule (if that works) or a second automatic action which follow the first.
Obviously not as nice as just having the one though...
Thanks for the reply.
I actually implemented the latter (Collections) method as I was also storing the count against each record there, so by doing a latest() on the collection and then incrementing the last count value read from there I could increment by 1 and save and thus achieve same.
So what I guess you are saying then it's legal to reference self by name even if it's not listed in teh selection tree? That's good to know.