"How else to explain the folly....?"

Actually the simplest answer seems the most likely. Just pure stupidity on the part of Saakashvili. He didn't think about the likelihood that Russia would not only throw enough military weight into the crisis that the Georgians would have no chance, but would also take advantage of the situation to strengthen the breakaway provinces in their separation from Georgia.

No conspiracy theory needed.   Why oh why are so many Mudcatters so enamored of conspiracy theories?

This one sounds like classic post hoc propter hoc.

That won't wash. We need some actual evidence. If Saakashvili himself has said something about an agreement for US backup against Russia in his move against South Ossetia, that would be something concrete. So let's have some direct quotes--if they exist.

Everything I've read indicates the US constantly cautioned him against his attack--and he ignored the advice.