Clary - OK opposite point of view to RosieT - sorry, no offence, but just to put the other side of the coin
I don't think one wet bed a fortnight is that great, and in winter it's such a pain to get linen dry, I would hate that. My ds always managed to wet the sheet, pillow case, pillow, duvet cover, AND duvet!
He was a deep sleeper, and was in bed 12 - 13 hrs, also very big, and in a top bunk, and with a weak back, I couldn't consider lifting him. Every morning his nappy was sodden. (He was dry in the day from when he was just 2).
Occasionally we would try him with no nappy for a few days, but it was just a flood. So we waited, and waited, and waited ...
Suddenly one day his nappy was dry in the morning, (he was just a couple of months off 5), and it was dry the next day too. So we left the nappies off, and that was that. Since then (almost a year), I can only remember one accident, though I've a feeling there might have been a second one too, but I can't recall it at present.
So there you go, my vote is for waiting, and that's what I'll do with ds2.