I have a question about keyword variations. To be specific, let's say "blue upside down cars" has low competition but fairly low traffic. However, the shortened variation "upside down cars" has low competition but extremely high traffic. Can I double my bet by going ahead and using "blue upside down cars" whereby in some instances Google would refer traffic based on the entire keyword, but it would also refer traffic based on the the last part of the keyword which has the higher traffic ("upside down cars"). In this case, we would optimize around "blue upside down cars" with hopes of getting traffic for both keywords (the long tail and longer tail).
Is there any reason not to pursue this strategy? I hope I made sense!