Was it a coincidence that the majority of contestants became super-cautious after the show became an hour long?? Did it have anything to do with the show's time slot expanding? You could go for months on end without any big wins after 2010 (well at least until box 23 was introduced anyway), and the "horrible deals club" ballooned in size, with a lot of "bad" deals post-2010 rivalling the likes of Richard and £1k Michael - Often it made 2008 not look so bad in hindsight
Obviously those last few months of 2010 showed signs that DoND was beginning to struggle financially, and i know the show had to try and survive on a reduced budget, but making the show an hour long to include so much useless padding and drawn out bits really felt like they were doing it in a desperate attempt to gain revenue through extra ads