The only way to fix it is to rent a miner..
The only way to fix it is to fix the coin actually. The diff will be jumping sky high until the ppl give up on this thing. Most of them already did.
How does one fix what's not broken? The system is acting exactly how it should act. Someone jumped on it with alot of hashing power, took the diff to 18 and left. The next time a block is found it will go back to min diff.
The roller coaster effect is a problem. The gravity-well protocol you used before is/was just a patch. It is obvious now that this coin has been doomed for the last 18 months. You should probably just pull the plug, and quit justifying what is happening as a planned feature. Perhaps you should examine the block explorer to see what is actually happening as a manipulation of this "feature."