Max drift formula is also very useful to quickly estimate how much you need to steer to remain on course. For 120 knots of TAS, which happens to be more or less the correct speed for a typical MEP used for IR training in the terminal area, you just need to divide the wind speed by 2. That gives your maximum drift you can possibly experience at that speed, then the clock formula comes in handy to further redefine your drift. For example, you've got a 30 knots wind 30 degrees off your course. Divide the wind speed by the nm/min (120 knots is 2 miles per minute) and you get 15 knots. It's 30 degrees off, so you experience a drift of 7,5 degrees, let's round it up to 8 degrees.
It works just fine for navigation. For a typical 90 knots cruise speed on a Cessna 150, you simply get 2/3 of the wind speed. In the example above it would be 20 knots, then you use the clock method to get to a final estimate.
It's not rocket science, really. In my opinion, those aptitude tests don't really reflect what a trainee goes through during his/her training. Heck, I passed GNAV and RadioNav by making simple sketches and eyeball which angle was bigger or smaller.