Every fan base is going nuts over Tanaka. I'm dumbfounded. In Washington, people are with a straight face proposing that the Nationals should acquire Tanaka and then trade Strasburg for a first baseman. This is the pro-Tanaka crowd's way of rebutting the "we need offense, not pitching" argument.
Tanaka went 24-0 with a 1.24 ERA in Japan. He's probably not that bad. But Japanese players coming over to MLB have been more miss than hit. Perhaps Tanaka is different because he's still relatively young, but I think the smart money is on Tanaka underperforming his contract.
It's true that the Sox don't have better ways to use that $20 million this year. There are no more desirable FAs left and its a while before the Sox have to worry about locking anyone up long-term. But keep in mind that Tanaka will likely command a long deal, and that $20 million/year might seriously hamper the team in a few years.
EDIT: The KW thing to do, of course, is wait until Tanaka underperforms with his first team, then snatch him up and have Coop fix him, a la Contreras.
The entire free agent market right now is insane, but this might be second only to the Cano contract.
"Hope...may be indulged in by those who have abundant resources...but its nature is to be extravagant, and those who go so far as to stake their all upon the venture see it in its true colors only when they are ruined."