Well, not really. My "driver" is very low level. It has less functionality than any other comparable driver. The only point is that it is extraordinary fast. Worst case is 40ms, best case <2ms. I was just hinting that you should consider to buffer your output in RAM. Since you will use the microcontroller as a graphics controller this should not be much of an issue.
With regard to the performance: I did no significant performance optimizations. Actually my goal was to have an as simple (and LCD independent) driver as possible. Since I figured that some LCDs can not be read I used the buffer approach. It then turned out that this gives impressive performance without any additional optimizations. If I would switch to assembler or start tuning it might get even faster. But then again it is already to fast for the display. As I said: worst case performance is currently 50 Hz 
I think it would be trivial to push it further by double buffering and only transfering bytes that actually changed. If you use a controller with 2k memory you might want to consider this.
I even found some displays (from EA) that come already with an controller. However the prices are prohibitve.
Cheers, Udo