I would expect to a large degree that the strong trading has a lot to do with it. This I base upon the massive increase in internet sales/trading this year. As part of my job we do monitor (or should I say get supplied info ) this side of the industry. It is also widely accepted that internet sales is going to increase year on year for another 5 years to a large degree. The stats only project 5 years in advance so I can only speak up to that point.
The Dollar was already weakened to around 1.7 when the RNS was released so you can expect that this was already built into accounts....