1. You throw your bomb with your right hand. Keep this in mind, and headcrabs will be a bit easier 2. If you zoom while jumping (not hovering), it doesn't slow you down. So you can hop around zoomed in and still moving at full speed, as long as you zoom out for an instant every time you hit the ground
No, you can't, but keeping in mind which side it comes from when you're up close or near a corner does help, it seems.
Along the same idea, assualts are right handed. So when you come around a corner you can alt. fire with your AR and be able to shoot things before they see you. IE a fire base right around a corner. You can kill the fire base w/o is shooting you.