I watched a good (5.5K?) phoenix play a 1v1 lane skilling 1-1-4-1 and just lasering his opponent at every opportunity (note that his opponent was a slark so melee range, limited escape, no stun/silence and not terribly vulnerable to fire spirits). Now it was offlane but the build was clearly due to the 1v1 nature of the lane. He got a few solo kills cuz laser is 270 dmg + 36% of MAX hp aka around a 65+% nuke to ur average hero at level 7.
however i'm sure thats obscenely situational since ur average mid hero is likely to have an escape, position well enough to be not laser vulnerable, be able to just nuke you down, or some combination of the 3. just a funny phoenix build that was very effective that I saw.