Since you are only considering the possibility that the light will make you a better target, ask yourself this:
Consider the amount of training you REALLY want if you be using a flash/move approach in the dark in your home - consider if you should even be doing that period as opposed to grab the gun, get to a choke point and call the popo.
Also, consider the vast majority of BG's - robbers who really do want to be shot. SO getting in a fight with a KNOWN shotgun is a bad idea to them.
Consider the likelihood that skulking around in the dark all amped on adrenaline the likelihood of tripping and accidental discharge, knocking things over and making a bunch of racquet, or just plain surprising someone who would have otherwise left. Oh yes - how about failing to identify a target.
Finally, show me just one example where someone said "Yeah - the BG was in my home and I had the light on. He triangulated the position of might light and opened fire. I got shot because of the light." And even if you do find ONE, all the rest were situations where that didn't happen. You are not combatting a bunch of former SEALS, SWAT, and other operators, and if you are they have night vision and you'll be dead.
I choose to turn the light on, leave it on and focus on one and only one thing - where is the target and go/no go. That is MORE than enough without getting all tactical fancy fancy.
I can reach the momentary switch on my light with my forefinger anyway. Not that I do...but I could.
Your decision may be different. Just something to consider.