The test plan was written assuming that the Quality Assurance group would be given ample time to perform all of the testing that was planned. Unfortunately as it turned out, due to delays in development and even in testing itself we were unable to complete most of the testing in the test plan.
Originally we had a Gantt chart outlaying testing progress but it turned out to be much too ambitious given team member's responsibilities and commitments to other projects.
The test plan did turn out to be very useful in providing guidelines and setting goals for the QA team to follow and strive for. Writing the test plan force the QA team to gain a more thorough understanding of the IFESS system which allowed them to make better more informed decisions on which tests to run in the time that they had.
Our troubles with adhering to the test plan essentially boil down to there being no defined separation between testing and development. The whole IFESS team had too many other responsibilities to other projects to commit the amount of time required to complete things according to plan.