Interesting attack indeed but h4xx0r who did you quote with the idea of giving to the next miner a share of your coinbase tx? It's trivial to give to the next miner outside the coinbase transaction by sending the reward as a transaction using one of the current inputs. Sure, then you have to scrape the bitcoins from elsewhere.

To recap the attack in laymen's terms:

If somebody paid 10,000BTC in transaction fees, miners would not care about block rewards for the next 10,000/25=400 blocks. Any miner that thinks it could outrun the biggest other miner would try to do so. If there is a draw between the top miners, such a battle could take a long time. If the top miners hold 10% of the mining power, they might try even when the other had a head start and was slowly building a chain that's growing faster than the own chain as they could still call their friends of other pools to team up catch that guy, essentially to the point where all miners took one side or the other and the weaker group gives up.

Also the attack does only work if the biggest selfish miner is bigger than the total of his run-up competitor with all non-selfish miners, so it assumes a pretty corrupt mining landscape.

The attack's effects:

During such an episode, massive re-orgs would happen, clients would act strangely, Finney attacks would be slightly easier etc. and we would have a slightly higher level of drama. And we will never know who sponsored that drama but it would not be a cheap endeavor.