There is no general rule stating you cannot modify a combat value of 0 above 0, and multiple SHIELD team members can boost 1 characters range up any number of times (capped by the Rule of 3, of course).
Quote : Originally Posted by disguy
yes to both. Though having a 1 range won't do you much good.
You could do this to shoot someone in a square next to a square you occupy that is on different elevation. Useful if you don't have leap/climb or such, and can surprise the heck out of someone.