Hey guys, here's a quick aside: one of the really neat things I've discovered during the set-design process is how much a certain part of it feels like your own personal Magic draft.
I'm talking about the point in time where you have too many cards for the set, and it's time to cut parts of it away. It's like what a sculptor must feel, given a massive block of stone and a chisel (or whatever tools a sculptor would use in that situation...) You have a great chunk of really nice stone, but much of it is standing in the way of the piece you want the audience to see. You cut and cut, and in so doing, you shape what's left into its purest form.
It feels like the point in a Magic draft when you have 27 good cards, but only need 23 of them for your deck. I'm horrible at making the choice of which cards to cut (I'm usually the last to finish), but it's also a big part of what keeps me coming back for more.
It's fascinating to me to have found almost the same sensation and process here, during set-design. The only difference is that it now carries the additional (and quite stirring) weight of the personal work, attachment, and ownership you feel to the whole thing. You have a much stronger bond with a card you've designed than you do with one you just opened in a pack. The only stronger bond (in Magic design, anyway) is what you feel with your whole set; if cool card X makes set Y worse by its inclusion, then you have to let X go.
Having a "Design File" where you can put all these bits and pieces that you chisel away makes the whole process much easier; even if you never end up using the card down the road, the fact that you *might* makes it easier to put the card aside.