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That's a VERY good summary! Thank you for finding it, forwarding it here to Free Republic.

Can they dump a bunch of graphite control rods into the reactor core and shut it down that way? Or have they already tried that by now? Just wondering.
From what I understand, it shut down immediately. But will take a LONG time to cool the core to below meltdown temps.

No, no, no, and again - no. You're thinking of a different kind of reactor (the Russian Plutonium-producing fast reactors like Chernobyl used graohite as a moderator, not a control of the reaction levels. In any case, the solid graphite could be pumped in since they wouldn't help and couldn't physically fit in this kind of control system.

The reactors are shutdown - that's NOT the problem. The problem is that fission reactors continue to produce a small, but significant amount of extra heat after you shut them. If you turn your car engine off, you can’t put your hand on the engine block immediately -> it's still hot. But you don't need to keep the oil pump running to cool it off, do you?

Now, imagine that you shut your engine off, but still need to pump a little bit of oil for 144 hours through the engine to keep it from breaking the bearings.

If you don't keep pumping this little bit of oil through the engine, the bearings break and it leaks engine oil all over your garage floor (into the containment building) but it won't get in your house, unless the garage gets completely full of oil, right? But the oil won't get into the yard and your neighbor's house unless it leaks all the way up to the window level in your house first.

Well, the engine is not running, so you need a backup oil pump to keep the oil flowing. You could use the house power, but that's out from the earthquake. You could use the car battery, but that is going to run down. You could use your gasoline generator, but that's broken because the garage fell down it. You could borrow your neighbor's gasoline generator, but his fuel tank got contaminated with salt water from the tsunami. You could use a manual pump, but that's too small.

So the Japanese engineers are trying to get that backup oil pump going before their battery runs out so they can prevent the oil from leaking out of the engine bearings. In the meantime, their garage floor is getting messy - and it will be an expensive cleanup!! - but the neighborhood is only threatened if the oil cannot be stopped AND a lot of other things go wrong.