Hell yes, finally. Yes, it can be done. I did it on Expert. It's just incredibly difficult. Let me count the ways...
- Firewire the guard by the door in front of you, who comes out to take a piss. Drag him just inside the door, take his clothes.
- Walk over by the guard in front of the garage, so you're just around the corner, and her turns to look in that direction (where he will stay).
- Go behind the garage. Very, very carefully, sneak up behind the first guard on the porch and anesthetize him. Drag him into the basement stairs on the side of the building. Make sure the delivery boy doesn't see you.
- Wait until the stupid postman delivers his flowers and leaves.
- Sneak up behind the second guard on the porch, the one with the shotgun. He needs only to be drug back a little ways on the porch, if you waited for the stupid postman to leave.
- Take the shotgun, and drop it by the door on the wall, by the dead guard.
- Go around the front of the building and in one of the back entrances. Wait on the stairs for the guard by the boss' bedroom to leave his post (which happens about every four minutes). When he starts to move, Save.
- As soon as the door he went through closes, quickly go into the boss' bedroom and on the balcony. Take a right, turn around, and get out your silenced 9mm.
- Wait for the boss to open the door, and shoot him in the back of the head. You only have one shot; two shots voids Silent Assassin. Get the key.
- Make your way down to the basement, see that the priest isn't there.
- Go out the way you came in, and remember to grab the shotgun.
I doubt anyone will use or even read this, but after spending two hours to figure it out, I wanted it recorded for posterity somewhere.