for over a year i've been trying to rank the 2 keyword phrases in my sig (chocolate fountain and chocolate fountains). we rank well in chocolate fountain business, sales, dealer, manufacturer, chocolate fondue fountains, etc. but NOT in the root words chocolate fountain. i've optimized and reoptimized. we have good inbound links. i can't get a handle on this.
recently after reoptimizing both of our key sites (http://www.buffetenhancements.com and http://www.chocolatefonduefountains.com) i managed to get #3 in yahoo, then slid to 8 and bounced up and down between 5 and 9 until yesterday. now we've slid to the 30's. same story in google. almost made first page (top of page 2), then bouncy bouncy for a week or so with a slide into the 30's.
i've been doing this for years and have never seen such a quick flucuation.