Not a dumb question...
The TST box is available with several different programs to suit different turbo configurations.
The standard program starts fueling at around 12psi and is 100% by about 24psi (I think)
There are two twins flashes, which will start fueling at 4-5psi and be 100% by 12psi.
The aggressive programs are better for spooling twin turbos or large singles. They can toast a stock turbo in a hurry.