Seek speed isn’t specified in “seconds,” but in “units per second.” It’s the distance the parameter cursor travels each a second, measured in parameter units.
As such, if your parameter was 100 units long, and its seek speed was 1, the parameter cursor would take 100 seconds to travel the parameter’s full length. Similarly, if its seek speed was 4, the cursor would take 25 seconds to travel the parameter’s full length.