Really can not quantify what is happening ...or is not happening. Last year when is was almost double the price there wasn't enough hours in the day, this year it's half the price with same if not better return it's not selling.
I think it is a mixture of four things:
i) the pre-Dec dash, and the pre-April mini dashes will have pretty much resulted in anyone considering solar either having gone ahead or made a conscious decision not to bother. It will take time for demand to build again
ii) the EPC rating has reduced the potential customer base
iii) the mass media coverage concentrated on the FIT being halved (time to recover the initial outlay being doubled, return on investment being halved etc.). There hasn't been similar coverage on the falling prices so many will still think in terms of 18-20 years before the FIT can cover the initial outlay etc.
iv) the sudden dramatic drop in prices could seem to many either to mean that the solar industry was significantly over charging before (which doesn't encourage trust in the industry), or the current prices are just not sustainable (which doesn't encourage faith that the company will still be around when you get your first FIT cheque)