Dear Oluf,
As I too aim to be stable at 500' on a daily basis, I am well aware of this
It seems to be a language problem here, as you seemed to suggest that the aircraft was idle all the way down to being at its "stable" criteria. Furthermore, our interpretation of the word "hesitation" seems to differ slightly.....
Nevertheless, I think you are out of order to be speculating about the cause of this accident, especially using the words that you did. Excuse me for having more trust in the AAIB then an engine icing enthusiast.
Can I also point out that this type of approach is not carried out unknowingly, but is highly encouraged due to fuel savings and noise restrictions in this part of the World? As mentioned before, min 160kts until 4DME or somewhere along those lines is the standard at London airports.
Dave