I recommend moving methods, used by others, like `assertElementTextEmpty` and `assertElementText` below methods, which are using them (tests in this case).

This would allow us to follow rule where main code is on top and sub-code which reveals implementation details is below it.

P.S.
And that seem to be all of the improvements I can think of regardless this test. Will be waiting PR for MinkSelenium2Driver and other drivers, that would use it.