And even if a number of the reported searches are from web masters that is still a bonafide indication of the popularity of the term. If a web master can think of it the probability is that ordinary mortals will also think of it.
One would think so, but it's not true.
Webmasters and SEOs think of anything they can think of that might be a good search query and they automatically query the engines for those phrases to see where they rank.
There are hundreds of thousands of phrases that appear to get "hits" or searches, when the only ones actually searching using those phrases are software such as WPG.
It's not a small or insignificant number of these automated queries. It's a ton and it totally skews the results. The phrases are no good to anyone, but the SEO who can show his or her client the wonderful high ranking he/she got for the phrases no one actually searches for.
J