IIRC there was a thread all about this, that was started in 2002 and always seemed to be re-surfacing every so often. The thread was started by Hornetboy. Ive tried searching for said thread to post here but i cant find it, perhaps some of the older threads got ditched when the forums were re-vamped.
If u ask nicely, one of the mods may be able to check the archives, if such things exist here, for the thread. I think it might have had a title like "RAAF aptitude testing" Fairly sure it was started by Hornetboy and full of great feedback from guys who had BTDTBTT.