The problem with dropping the oil pan and re-sealing is that it's not a guaranteed fix.
- Firstly, the problem is that the there was too much sealant applied. If a computer controlled robot in a factory hasn't been able to seal it properly, then it seems just as likely that anyone who decides to do it themselves, lying on their back, in their own garage, will also be at risk of applying it incorrectly. And thus reattaching their oil pan thinking they've solved the issue, when perhaps they haven't.
- Secondly, I'm pretty sure that evidence has been found of sealing material of a different colour, which means it's not just come from the sump/block interface, but possibly from somewhere else (heads, cam covers, etc). If that's the case, there's no way of rectifying that without tearing the engine down completely.
Having said that, I think perhaps we should all step back and calm down about this. Although lots of people are reporting sealant debris in their oil pans, there have actually only been a few instances of engine failures, and only one of them that we know of where the warranty was initially refused (and that was not Toyota's fault, but the fault of a rogue dealer really). I am not going to lose too much sleep over it. I'm just going to drive the car and maintain it to the best of my ability. If the engine goes pop, it will be covered by warranty.
The good thing is that the controversy over the case in America is that Toyota wont really have a leg to stand on refusing any such claims in the future - not that I think it would be a problem anyway. As I said, that case in particular seems to be more about a shitty dealer, than the corporate response.