Checkerboard,
Ta muchly for the explanation, that's cleared up a lot of confusion on my part. As a civvy(ish) instructor teaching JAR PPLs at a RAF base we have all sorts of problems when the UAS come to visit. Of course they like their "initials" join but we don't teach it and this can cause conflictions in the circuit (I of course apologise most humbly and profusely to all the CFS instructors for even daring to occupy the same airspace as them).
The procedure seems sound to me and certainly less laborious than the overhead join but I do think it would be dodgy in an uncontrolled enviroment (although the Americans have their own variation at Unicom fields i.e. the join on the '45). Another problem arises because I have heard different people give different explanations of where they think "initials" actually is.