Smart Timer Technology works with Time Check. If you have Time Check turned on then by default then Smart Timer will be activated. If you don't wish to run this feature then you can go to "Timer Settings" and unchecked Smart Timer.
Along with the Smart Timer are two features called "Timer Boost" and "STX". These two features work with Smart Timer to enhance it's function.
What Smart Timer does is analyses your computers clock speed then adjusts Job Timer to compensate for that speed. It remembers what these settings are so Job Timer will run at maximum proficiency. The more Job Timer runs using this feature the better Job Timer will run. This really isn't noticeable too much to the user it just looks like Job Timer is running fine if you have it on or off. The only way you see it working is how much the status bar has moved. If you have been working on a project for several hours and that status bar hasn't moved much then your computer is already optimized, but if that status bar has a noticeable increase, then Job Timer has done the optimizing for you.
Timer Boost will increase the Smart Timers function to reach it's goal faster. This will decrease the amount times that Time Check will have to work.
STX will keep Smart Timer in check and not run overrun the clock.
More on Time Check can be found here.