We do extensive tempo from the very beginning…especially the long sprinters, who do it 2x / week. The short sprinters do it 1x / week.
We do tons of GS year round. The overall volume doesn't vary that much. It pretty much stays the same (+/- 10%) all year round. I just switch up the actual series of exercises and sometimes the means of execution. I kinda view the low intensity GS work as the 'glue that binds things together.' It's a critical component of my programs.