Jim,
Almost certainly in the wrong place at the wrong time...and yes, the drift seems to be with such a small quantity of water, that it perhaps layered or was picked up all at once due to the change in attitude during the latter stages of approach.
It's interesting to note that one of the recommended changes in operational procedures may be to vary throttle settings more before or during descent (the implication being I think, so to stir up or purge wtaer/ice near the scavenge pumps)
A question I put on one of the early pages of this thread was along the lines of
'... is it really possible that the throttles might not have been moved from the top of descent right up utnil the drag increase of landing configuration took place'
The answers to that were along the lines of... 'Yes, quite possible, and there has even been a move towards that situation due to approach profile that specifically encourage it' (fuel usage and noise abatement I believe)
[please clarify or correct if you feel this is wildly inaccurate, I haven't re-scanned those responses as yet]