Think about it this way. Current net hash is around 50ghash average and after new filter is in place the dif drops immediately 1/4 making the optimal net hash 250ghash as opposed to somewhere over 1thash. This would bring block times down to about 50 minute blocks on average if we sit at 1/5 recommended network hashrate (50 now to the new 250 optimal) and that will drop 5%ish every 9 blocks until the dif meets net hash to get 10 minute blocks cranking out.

And when the dif drops to 1/4 of what it is now, the profit calculator on dustcoin will show near 85% profitability due to new lower mining dif. As the dif further lowers to adjust to net hash the profitability will continue to rise along with more miners coming back to the network and hopefully the price for FRC increases as it becomes traded more again.