For that purpose you should use airdriver-ng.
Thanks for the pointer to this utility TP - I had missed it entirely !
Reading the man page for airdriver-ng at the home site, it says it needs internet connectivity to download, compile and install the patched drivers, but this page
http://trac.aircrack-ng.org/ticket/438indicates that this is impossible with wireless-only connections (they set the bug to 'wontfix').
The laptop I am using to build this system has no wired ethernet, so it's USB wireless ONLY - which means manual download/compile.
aircrack-ng as in repo does function correctly with compatible drivers as in repo.
Not for me, I'm afraid - the stock Core Plus with aircrack-ng from the 4.x repo errors out with the 'Channel -1' bug for a Ralink RT3070 USB stick - so something needs patching somewhere - which is why I asked the question in the OP. lsmod shows that rt2800usb is loading, as expected.