Rory,
Just like everything else in aviation, it's all about compromise. Firstly, a good stabilised approach will have eveything dangling and sorted out, which means that the aircraft is nicely trimmed so that only minimal inputs are required to fly the aircraft accurately. Contrary to much maligned public thinking, total engine failure approaches aren't really considdered within any flight training environment until the crew have become much more experienced on the aircraft type. All-engine flame-outs are indeed practiced, but normally at high altitude so that the crew can practice emergency engine relights... should a relight not happen, on any engine, you're then obviously committed to that very rare emergency procedure of actually having to land the beast somewhere. I recall an Airbus running short of gas over the Atlantic (a fuel leak) and carrying out a successful approach into the Azores; also another dead stick landing into an airfield in Canada... both very well handled by experienced crew.
If we were to routinely carry out 'high energey' approaches as a matter of course, I feel sure that there would be many more incidents than there are today, because believe me, trying to keep a big heavy aircraft in-trim and under control during that final slow-down and getting the gear and flaps out requires considderable skill and concentration. High rates of descent at low altitude whilst trying to control that other aviation dimension - that of inertia - is an artform in itself and not recommended.
Just to clear up the 'landing gear' misconception that was previously mentioned. Raising the gear does indeed cause quite a large, initial, drag penalty, because the gear doors have to open prior to the gear coming up and it's those doors which cause that increase in drag. Once the gear is safely tucked away and the doors have closed then of course it's a much cleaner airframe. As an example, for most aircraft which are carrying out a windshear recovery procedure (particularly close to the ground), most airline procedures recommend that you do NOT raise the gear until you have achieved a satisfactory airspeed and climbing away from the ground/encounter. The very reason for this is because of the extra drag caused by the gear doors opening, which would negate what you're trying to acheive... gain airspeed!
Hope this helps.
TCF