Very interesting thread... I decided to let it develop a bit before I added my thoughts, and I'm glad I did, because it's turned up some interesting points.
The original question was re. single-engined aircraft. The only way to guarantee that you'd be able to make the field if you had an engine failure is not only to do a glide approach, but to use a bit of side-slip. If you plan a perfect glide-approach without side-slip and the engine quits, the extra drag from the stationary or windmilling prop will bring you down faster than you'd planned, and you'll land short. How many of us do this every time (tail-dragger pilots who need to side-slip to see the runway are excepted!)
How necessary this is depends on the field. As AF said, there are some airports/runways where there are no alternatives. I always try to be high on 25 at White Waltham, because if the engine quits on short finals and you're not high, you're in the houses. On other runways it's not so important, because there are places to land safely short of the runway - but even then, there's not really any advantage to a shallow approach. And a 3-degree airliner approach just seems really stupid in a PA28.
The mutli-engined situation is causing more arguments though. Before I give my thoughts, I need to say that I don't have a multi-engined rating - this based on just 5 hours of dual in a twin. But the point which people are arguing will make things difficult is the low power setting on the remaining engine. I don't know about the rest of you, but I was taught that the first actions on an engine failure are gear up, flaps up. Then, mixtures rich, props forward, and throttles open. Once you've opened the throttles, you should have no problems identifying the dead engine, but even so the next steps are to identify, verify and feather - so even if you get it wrong, you've got a chance to realise it and correct your error.
What I'm not sure about, and I'd appreciate some input from the experts here, is whether you'd have time to do all of these steps on short final. In fact, would you even want to put the gear and flaps up? Given the poor single-engine performance of many light twins, it may be that once an engine quits, you're commited to land, in which case you certainly wouldn't want the gear up. But I can't see any reason not to open the throttles, and then verify the dead engine by closing the relevant throttle, before feathering a prop - and it seems like these two steps would solve all the problems people are talking about here.
FFF
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