In part this was because updating the size estimator in some cases required considerably more work than making the actual bug fix or improvement, and the developers had many urgent changes that needed to be made to the core software in this period.
another difficulty with building an estimator that predicted the behavior of the microplanner, realizer, and Word was that it was difficult and timeconsuming to maintain the accuracy of the estimator as changes were made to the microplanner and realizer, and also to the exact RTF structures produced by our system for Word to process.