removing 15mm from the fork will rotate the whole bike about the the rear hub which acts as a pivot point. This will have rotated the BB, bars & saddle forward and down (the amount they move is relative to the distance from the rear hub). Presumably ed has adjusted his saddle so that it's in the correct position relative to the BB. So now he needs to compensate for the change in saddle to bar height and reach. I'd do this with a new stem rather than some weird head set/fork magic. Or get a new fork that fits :-)
removing 15mm from the fork will rotate the whole bike about the the rear hub which acts as a pivot point. This will have rotated the BB, bars & saddle forward and down (the amount they move is relative to the distance from the rear hub). Presumably ed has adjusted his saddle so that it's in the correct position relative to the BB. So now he needs to compensate for the change in saddle to bar height and reach. I'd do this with a new stem rather than some weird head set/fork magic. Or get a new fork that fits :-)