Wow. I just can't see what you are seeing. I can't fathom how someone can look at that picture and believe Red is ahead of Grey.
OK, now I'm agreeing the code needs to be updated. If a bunch of experienced skiers like us can't agree about which skier is ahead, the language needs to be clarified. No wonder there is chaos on the slopes.
I would consider Gray "ahead" of Red in picture 2 BUT I recall someone defining "ahead" as being closer to the other skiers toes than heels. Using that definition, aren't they both "ahead" of each other. If you can't agree on that based on photo 2, then picture a situation in which they are equal with each other on opposite sides of the slope and traversing towards the middle. Who is "ahead" then?
Point 2 of the code (People ahead of you have the right of way. It is your responsibility to avoid them) should not supersede point 1 (Always stay in control, and be able to stop or avoid other people or objects.)
Now how does one learn the parts of the code that are not included in the 7 that are commonly written? (from http://www.nsp.org/slopesafety/respcode.aspx) (I think I will start a new thread on this topic unless everyone thinks it belongs here)
Know the code. It's your responsibility.
Note* This is a partial list. Be safety conscious.
This is why I think a skier like Gray should be looking over his shoulder as he swings left.