A recipe for disaster in my opinion. I came across QNE the other day, the altimeter reading of the airport when the subscale is set to 1013......
I learned a little trick several years ago, it entailed looking up the airport elevation BEFORE getting airborne . This allows me to land at an airfield which is not at sea level WITHOUT (yep, thats right) setting QFE.
I suppose I'm missing out on a lot of the altimeter twisting fun though. Just think, on a cross country, you first set QNH on one altimeter, and QFE on the other. You transition above the Transition altitiude and you now twist one to 1013, and set the regional QNH in the other. but hold on a minute, you now need to cross a class D zone. This may require the 1013 altimeter to be set to a local QNH, as the transition level may rise to > your FL. So you exit the zone, and reset regional QNH, but now you want to transition a MATZ. You are passed QFE, which you must now set, until you are clear and then you go back to regional QNH. Ok, you're now descending into your destination, you are passed QNH and QFE which you set. the weather is a bit crappy, you're turning base....hmmm, did I set QNH or QFE........