I'm surprised we haven't had an "expert" view on this yet - maybe it's worth posting a link to this thread on the Technical forum? But, for what it's worth, some more uneducated thoughts from me regarding stalling:
Remember, when you're stalled, you're still doing (depending on aircraft type, of course) around 50kts. You could approach at, say, 10% above the stall speed, and it really wouldn't make that much difference to the total amount of energy the aircraft has at impact.
If you fly nose-first into the water, all the deceleration will be horizontal relative to your body - this is the direction in which the body can withstand most force. If you approach nose-high, when the tail impacts, the nose will be forced down with considerable vertical force, which the body is not capable of withstanding.
It really would be nice to hear the "real" reason why the advice is to fly into the water - the reasons I'm giving are from logically thinking the problem through, but I haven't read that much on the subject, so it wouldn't surprise me if I'm completely wrong. But one thing I do know is that all the advice I've ever read, whether in books, POH's or magazine articles, is to fly the aircraft in - and I doubt that everyone would be giving the same advice unless there was a good reason for it.
FFF
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