The thing that is important to understand about this rule is that it only covers free air time given by a station to a candidate. Therefore, there are lots of ways around it.
The easiest way that a candidate can get more coverage simply by being more famous and therefore more likely to get on TV. If Mitt Romney and a Green Party candidate both visit a diner for a photo op, Romney is much more likely to be covered. This would not count in the equal time rule because it is news coverage. Candidates who are more famous and have more support are also more likely to be included in debates, which also do not count under this doctrine.
This rule really does not cause any sort of true equality in news coverage of candidates. Instead, it covers only free air time given to candidates, which is not usually very significant.