In my police academy they reviewed the rolling the light on the floor... It would be one way to clear the room while holding the gun and manipulating a door knob/lock at the same time. But this method is very clumsy.
My academy being out in Rangely Colorado - if you cant find it on your map - It is in the north west corner of the state - They trained us for more of a rural environment. Officers quite often have as much as a 30 minute eta for back up out there. I at one point was a candidate for the position of Marshal of Dinosaur, Colorado. A one person department. Rangley, Colorado - also the closest Ambulance and backup unit was 30 minutes on the dot. Not too uncommon out west in small population - high milage locations. They trained us to do every thing alone.
(I'ld like to hear from some officers that are out in those types of places. How do you do it every night?)
A lot of the training focused on the aggressive style - to overwhelm the subjects and move fast to take perps unprepared. It is hard to overwhelm any thing alone. But that was the idea. Another factor that aids this is your uniform. Your image plays a big part in the mental reactions of the subjects your dealing with - When alone we would often wear black tactical styles, with black ball caps and low slung holsters. This was a bigger help - we looked ready to fight and we looked like we were good at it too.
Flash lights - I still wish I had had a UTL back then. That would have solved a lot of problems.