I'm not sure if this will be helpful to anyone, and I don't do speedruns or anything, but I figured out how to get the Flamethrower without the Redcoat and the Drone Teleport without the Address Bomb.

Basically you need to grapple to the 2 square surface below the entrance to each of these places and then go up as high as you can on the grapple. Then start the swing animation but don't actually jump. When you are close to the ceiling in the animation dash up with the Trenchcoat and it will let you pass through the surface as it normally wouldn't.

Hopefully someone can implement this into a speedrun if it hasn't been already.

Have a nice day.