Carlos Santana: spiritual mystic, guitar legend, pop music joke. It wasn't long ago that he swept the Grammy's, winning just about everything from Best Album to Best Polka Song featuring a Lemur on Drums. What's impressive, besides his guitar virtuosity, is that he is both revered and derided by the music-listening world. My theory as to why his career first went astray and then fell back into the gutter is that he (like Clapton and Slash) really needed a solid song-writing partner.There are moments though when everything seems to click for Santana. He had his "Oye Como Va" and "Black Magic Woman," and then on this relatively obscure and generally awful album from the 1970s called Festival (a festival mostly of horrors), he drops a wicked instrumental to make us weep at our inadequacies."Revelations" is crescendo rock, and after about three minutes of solid build, which includes legato keyboards, bluesy guitar, and a marching-band beat, it climaxes with incontinence inducing guitar and keyboard histrionics backed up with latin rhythms.