fireflybob and others. Many thanks for the comments. I appreciate that in this case different controllers have different ways of issuing an instruction but it's probably born from experience - ie issuing the one they think will work. Orbits, circles, 360s and other "leaving hold" type instructions aren't fully covered by our bible! Given a "continue right onto..." instruction I think most of my colleagues would expect a pilot to do just that, rather than turn towards the VOR. It's particularly noticeable at BNN in a northerly wind.. as they turn outbound we say "continue right to 130" and at least 50% will then turn north until they are north of BNN and then go through strange gyrations to get back over the VOR before heading 130. Meanwhile we've snatched three other a/c to fill the slot.