In actuality, the Spanish FIT for PV was already recuced more than a year ago, leading to a brutal bust in 2009. What you propose, an immediate slashing by half, would amount to a similar bust. To keep the market (and factories' steady output) alive, a more orderly reduction would be okay, say -10-15% each year or half-year. For planning security, it would be best if these degressions are known in advance for at least a year; but the Spanish FIT rates are re-set each year.

_{*Lunatic*, n.
One whose delusions are out of fashion.}