No, not pontificating at all. That's very helpful. Thanks for taking the time to sketch that up and explain. Yes it makes sense. I think something along the lines (so to speak) of 1 is what I was thinking, but as you say the end result will depend on what precisely my boy has in mind. (I was thinking curve but a straight line might better fit the angularity of the explorer theme.) But we'll stay away from the likes of 4. Cheers