A couple of questions regarding your questions.
1. Why are you assaulting the room?
2. Are the people inside armed and violent, intent on doing you harm?
3. Are you assaulting the room as a good guy or a bad guy?
4. Do you HAVE to go in against armed and violent people, have you any other options?
5. Do you have any control as to what time of day you make entry?
6. Is this a military or police operation, they have different rules of engagement.
The easiest question first - lighting. If you are going to go into the unknown, and engage a hostile target, you need to be able to see the target. Therefore, your tac-lights are on. You may also want to sweep the wall with your free hand on entry to activate a light switch. Your speed, training, and tactics should overcome the BG's ability to see you. Just remember, you can't hit what you can't see.
Don't use the light in the hallway prior to making entry so you don't give the BG's inside the room notice of your impending action.
The only other thing I will address without further info is a caution not to get too hung up on "I go right, you go left." The first person in the door should automatically address the most significant threat first, and the second person goes the opposite way.
I didn't do it, but I thought about it. Next time I might.