Robert_Charlton - 6:54 pm on Nov 21, 2011 (gmt 0)
...I would definitely have the phrases blue autos, blue automobiles, blue vehicles, etc., on that page as well....
I would be extremely careful not to overdo this.
Ditto, I would not overdo the synonyms, either in the nouns or in the adjectives. Too many synonyms might well look like keyword stuffing when Verbatim Search is turned off and the synonym recognition and co-occurrence factors are dialed back up.
Consider instead what a naturally occurring vocabulary distribution would be when the page is actually about the topic on which you're focused, in the context you're discussing. A page about cooking turkeys might include mentions with specifics of oven temperature, roasting, stuffing, cranberry sauce, etc. A page about turkeys in the wild might discuss specifics of feathers, mating calls, habitat, and competitive species.
But to have the page about cooking turkeys excessively repeat the word "turkey"... as in "turkey roasting", "turkey stuffing", "cranberry sauce on your turkey", etc, would be just plain silly. This kind of repetition simply doesn't occur naturally.
I think that phrase-based indexing forces you to be a lot more subtle in how you target phrase variations.