Now that I know for certain that you are seeing this, I will make sure not to Arilou, and also anything in the future.
Of course, Rarkvar, I am sure that the stats aren't actually that, although it is clear that I forgot just how quickly multipliers add up. Maybe doing 3x the normal damage would suffice?
Anyway, I can't imagine obsidian forming in the massive quantities shown in your map, and if there were a spot, I think it would be a good time to consider investing in some pickaxes rather than wasting your weapon. The danger of not having your preferred weapon readied would be a... risk, shall we say? And the extra investment in different digging materials would be an... investment. One suitable for earning obsidian by breaking through walls? Of course, if that idea were scratched, I would certainly say Obsidian shouldn't do extra damage to your weapon, but rather should have more health as per the original idea.
This all brings up another thought - Why can't those low level mines be redone for high level players, but with an obsidian theme? There's another random idea for you, although that belongs in another thread.
Now for your image. I got very excited when I saw there was one - overkill or not! It is really cool to be able to physically see the general idea come to fake-life. I had some ideas too, but my map editor crashed, and now will not fully load.