Brian is brilliantly mad. He has worked in P4 and P87, but decided that Märklin's MiniClub Z-gauge was much too rough, so he came up with Proto-220. That's finescale Z, with correct clearances through pointwork and wheels turned down to correct width and flanges.
He brought a demo P220 board to one show years ago, and all the pointwork worked flawlessly. This was in the days when my eyes could still focus on things that small.
Completely mad.