The answer to this question really needs to be answered on a
case by case basis. With a high budget,
I have seen campaigns as targeted as one keyword per group. This allows ads to include the exact search
term, which can increase quality score.
With a smaller budget this is probably not necessary, but with high
spend, even a slight increase in quality score can mean a lot of saved $$$.
This extremely granular strategy generally makes more sense
on generic non-brand keywords, as you are likely to be facing higher
competition. Even still, the best
solution to increase quality score remains a relevant landing page with high