One strategy which has performed very well in this sector, and in others with a few players making up the vast majority of a defined market, is a "Dogs of the Dow" strategy. By buying the worst performer in a previous year, investors have access to the potential reversion toward the mean that should drive all companies toward some sort of level over time.
This strategy assumes two things - that the capital depreciation of a given stock over a period of the previous year is likely to revert toward a gain in the current year, and the correspondingly high yield will provide much of the higher-than average gain during the current year.
Looking for value among dividend companies is always a good thing - finding companies with artificially high yields due to lower than average price appreciation (or declines) is an excellent way to attempt to have higher than average returns over time.