NDB 'Gates', 'Half Gates'?? This smacks of some old dinosaur teaching relevant to the DC2 and lovingly cherished by those who would make an art form of what is a NON-PRECISION technique! Like the teaching of some who agonise over how long to wait after crossing the beacon on an extreme sector 3 join before starting the downwind leg. 'Thousand one, thousand two.....now' or 'One Crocodile, Two Crocodiles....TURN' serve as well as 'the sine of the inbound angular difference multiplied by the date divided by the TAS expressed in furlongs per fortnight' or whatever. Remember K I S S !!
Heresy? Perhaps - but the NDB hold is NOT the be all and end all of IFR flight, just a very minor part of it. So let's keep it in perspective.....and it is NOT a mandatory part of the IMC Rating Test, although if ATC direct that a hold is required, then the applicant shall do so correctly.