I hesitate to recommend room clearing as the tactical advantage always lies with the one who remains silent and concealed. A snot-nosed teen with a Saturday night special can easily defeat a trained police officer when firing from ambush.
The exercises are fine and do build confidence. However, If I'm certain an intruder is in my home, I plan to arm myself and wait for him to come to me. I'll also call 911 and ask for the cavalry if I have that option. I've learned from years of deer hunting that I can often defeat a deer's superior senses through silence and remaining motionless.
Int'l Assoc. of Law Enforcement Firearms Instructors