The way I see it is, if you keep a constant turn during the holding pattern and choose to double the inbound drift for the outbound leg, then you only have one variable, the amount of drift you have applied. Therefore if it doesn't go quite your way you only need to adjust the drift angle for corrections.
If you choose to adjust the AOB during the turn as well as double your drift on the outbound leg, then you now have two variables, the AOB and the drift angle. So when it doesn't go quite your way, do you adjust the AOB in the turn or the drift angle or both???
For this reason I choose to double my drift angle and fly a constant AOB.
There are obviously other ways such as no or a constant drift angle and choosingto adjust your variable of the AOB.
From my experience whatever works for you and is safe and legal is ok.
Nice to see a student questioning procedures, it shows that your thinking, you don't see much of that anymore!!!