You cannot get a zero-size feedback delay in Pd at all, regardless of subpatch ordering or creation order. The subpatch-stuff only is valid for non-feedback connections. The best you can do is do a [block~ 1] or [block~ 8]

Sorry, I forgot to mention that I used [block~ 1] objects within the throw and catch modules. I found that the creation order was important though: The patch wouldn't work unless I instantiated the abstraction with 'catch~' in first- I guess because data cannot be 'thrown' to a bus without it existing first...

K