One difference which can affect this situation is aircraft type. As has been previously stated it's splitting hairs and in the great scheme of things it won't make a significant difference.
But on the B737-800 I fly at the moment let's say you are going to XXX (no holding) and the route is programmed to fly to YYY with a large track change then the FMS will work the geometry and start the turn early so as to roll out on the next track without an intercept or overshoot. So let's say we are asked to "Leave XXX heading ZZZ" we would usually select this heading ZZZ as the a/c starts the programmed track change to YYY. Depending on the Heading change versus the programmed track change you may or may not overfly the fix on the new heading - are you with me so far?
When I flew the A320 track changes at waypoints were more or less the same (although I recall that it would use about 5 degrees of bank and therefore start the turn earlier and cunningly cut the corner to save fuel) but the pilot could also select an option to "overfly" the waypoint before turning if one so wished.
Phew, I knew there was a reason why I woke up early for my dawn patrol this morning!
Last edited by fireflybob; 23rd Jan 2009 at 19:14.