Great article by Patrick from MS Developer Support, he explained a hidden DEX.ini switch that reduce the time needed to export data from Smart List to Excel, by his words:
I pressed the Export to Excel button and Smartlist exported the 10,000 rows by 7 columns in 1 minute, 55 seconds (115 seconds).
Since this switch is read on the fly, I didn't have to restart Dynamics or even refresh the Smartlist. I just pushed the Export to Excel button again. How long was the export this time? Would you believe 9 seconds?
This magical feature will be enhanced by just adding the following switch to your DEX.ini file:
Take a look to the complete explanation about the switch in the Developing for Dynamics GP Blog.