Couldn't this be easily stopped if there was a limit on the difference between two blockchain heights was put into effect? because as far as I know the litecoin client currently accepts the longest chain as the most valid one. So this would prevent something I would call "chain hopping" on the client.
The only way to stop it is to do what solidcoin did and have "tyrant nodes" where they need to sign the blocks to be valid but unfortunately that is a centralised solution.
